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• Cisco 678 Will Not Work using PPPoE - Possibly Because I Configured it Incorrectly..?

  - by Brian Stinar

  I am attempting to configure a Cisco 678 because I am totally sick on my Actiontec. However, I am running into some problems. It seems as though the Cisco is able to train the line, but I am unable to ping out. I am all right at programming, but still learning a lot when it comes to being a system administrator. I apologize in advance if I did something ridiculous, or am attempting to configure this device to do something it was not designed to do. It is almost like I am not correctly configuring the device to grab it's IP using PPPoA (like my Actiontec.) The output from "show running" (below) makes me think this too. Below are the commands I ran in order to configure this: # en # set nvram erase # write # reboot # en # set nat enable # set dhcp server enable # set PPP wan0-0 ipcp 0.0.0.0 # set ppp wan0-0 dns 0.0.0.0 # set PPP wan0-0 login xxxxx // My actual login # set PPP wan0-0 password yyyyy // My actual password # set PPP restart enabled # set int wan0-0 close # set int wan0-0 vpi 0 # set int wan0-0 vci 32 # set int wan0-0 open # write # reboot Here is the output from a few commands I thought could provide some useful information: cbos#ping 74.125.224.113 Sending 1 8 byte ping(s) to 74.125.224.113 every 2 second(s) Request timed out cbos#show version Cisco Broadband Operating System CBOS (tm) 678 Software (C678-I-M), Version v2.4.9 - Release Software Copyright (c) 1986-2001 by cisco Systems, Inc. Compiled Nov 17 2004 15:26:29 DMT FULL firmware version G96 NVRAM image at 0x1030f000 cbos#show errors - Current Error Messages - ## Ticks Module Level Message 0 000:00:00:00 PPP Info IPCP Open Event on wan0-0 1 000:00:00:14 ATM Info Wan0 Up 2 000:00:00:14 PPP Info PPP Up Event on wan0-0 3 000:00:01:54 PPP Info PPP Down Event on wan0-0 Total Number of Error Messages: 4 cbos#show interface wan0 wan0 ADSL Physical Port Line Trained Actual Configuration: Overhead Framing: 3 Trellis Coding: Enabled Standard Compliance: T1.413 Downstream Data Rate: 1184 Kbps Upstream Data Rate: 928 Kbps Interleave S Downstream: 4 Interleave D Downstream: 16 Interleave R Downstream: 16 Interleave S Upstream: 4 Interleave D Upstream: 8 Interleave R Upstream: 16 Modem Microcode: G96 DSP version: 0 Operating State: Showtime/Data Mode Configured: Echo Cancellation: Disabled Overhead Framing: 3 Coding Gain: Auto TX Power Attenuation: 0dB Trellis Coding: Enabled Bit Swapping: Disabled Standard Compliance: T1.413 Remote Standard Compliance: T1.413 Tx Start Bin: 0x6 Tx End Bin: 0x1f Data Interface: Utopia L1 Status: Local SNR Margin: 19.0dB Local Coding Gain: 7.5dB Local Transmit Power: 12.5dB Local Attenuation: 46.0dB Remote Attenuation: 31.0dB Local Counters: Interleaved RS Corrected Bytes: 0 Interleaved Symbols with CRC Errors: 2 No Cell Delineation Interleaved: 0 Out of Cell Delineation Interleaved: 0 Header Error Check Counter Interleaved: 0 Count of Severely Errored Frames: 0 Count of Loss of Signal Frames: 0 Remote Counters: Interleaved RS Corrected Bytes: 0 Interleaved Symbols with CRC Errors: 1 No Cell Delineation Interleaved: 0 Header Error Check Counter Interleaved: 0 Count of Severely Errored Frames: 0 Count of Loss of Signal Frames: 0 cbos#show int wan0-0 WAN0-0 ATM Logical Port PVC (VPI 0, VCI 32) is configured. ScalaRate set to Auto AAL 5 UBR Traffic IP Port Enabled cbos#show running Warning: traffic may pause while NVRAM is being accessed [[ CBOS = Section Start ]] NSOS MD5 Enable Password = XXXX NSOS MD5 Root Password = XXXX NSOS MD5 Commander Password = XXXX [[ PPP Device Driver = Section Start ]] PPP Port User Name = 00, "XXXX" PPP Port User Password = 00, XXXX PPP Port Option = 00, IPCP,IP Address,3,Auto,Negotiation Not Required,Negotiable ,IP,0.0.0.0 PPP Port Option = 00, IPCP,Primary DNS Server,129,Auto,Negotiation Not Required, Negotiable,IP,0.0.0.0 PPP Port Option = 00, IPCP,Secondary DNS Server,131,Auto,Negotiation Not Require d,Negotiable,IP,0.0.0.0 [[ ATM WAN Device Driver = Section Start ]] ATM WAN Virtual Connection Parms = 00, 0, 32, 0 [[ DHCP = Section Start ]] DHCP Server = enabled [[ IP Routing = Section Start ]] IP NAT = enabled [[ WEB = Section Start ]] WEB = enabled cbos# wtf...? Thank you all very much for taking the time to read this, and the help.

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• e2fsck / resize2fs problems

  - by BlakBat

  I've got 6 drives (each 1.5T, all same model and firmware revision) that are part of a RAID5 array. The RAID5 makes a LVM volume group and a logical group. The latter contains only one ext3 partition. I've recently ran: e2fsck -f /dev/vg03/lv01 && resize2fs -M /dev/vg03/lv01 which exited without an error. Now when I try to mount /dev/vg03/lv01 I get: EXT3-fs error (device dm-0): ext3_check_descriptors: Block bitmap for group 30533 not in group (block 1000532368)! EXT3-fs: group descriptors corrupted! How do I get out of this predicament? This is all the info I can currently give you: fdisk -l /dev/sd[cdefgh] shows (correctly) that they are "Linux raid autodetect" but fdisk now shows: fdisk -l /dev/md0 Disk /dev/md0: 7501.5 GB, 7501495664640 bytes ... Disk identifier: 0x00000000 Disk /dev/md0 doesn't contain a valid partition table (instead of a LVM type partition) fdisk -l /dev/vg03/lv01 Disk /dev/vg03/lv01: 7501.5 GB, 7501491732480 bytes ... Disk identifier: 0x00000000 Disk /dev/vg03/lv01 doesn't contain a valid partition table (instead of a ext3 type partition) I've tried: e2fsck -fy /dev/vg03/lv01 e2fsck 1.41.12 (17-May-2010) e2fsck: Group descriptors look bad... trying backup blocks... Block bitmap for group 30533 is not in group. (block 1000532368) Relocate? yes Inode bitmap for group 30533 is not in group. (block 1000532369) Relocate? yes Pass 1: Checking inodes, blocks, and sizes Relocating group 30533's block bitmap to 1000524246... Error allocating 1 contiguous block(s) in block group 30533 for inode bitmap: Could not allocate block in ext2 filesystem e2fsck: aborted Extra information I can give you: cat /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active (auto-read-only) raid5 sdg1[0] sdh1[5] sdf1[4] sde1[3] sdc1[2] sdd1[1] 7325679360 blocks level 5, 128k chunk, algorithm 2 [6/6] [UUUUUU] bitmap: 1/175 pages [4KB], 4096KB chunk unused devices: Lastly, all smartctl tests (short and extendend) showed no errors on any of the disks. Should I try to resize2fs to grow /dev/vg03/lv01 and redo a e2fsck ? Should I cfdisk /dev/md0 and /dev/vg03/lv01 back to their real types? Thanks in advance for all and any help. 2011-09-20 UPDATE I issued the following commands and was able to remount the partition, but by viewing the size (df) of before and after, it seems that 1Tb of data have gone missing. By checking the MD5SUMS (from an old backup) of some files with the "same" files from the remounted partition, some errors have been detected. Commands issued to remount the partition were: dumpe2fs /dev/vg03/lv01 Block count: 1000491435<br /> Block size: 4096<br /> tune2fs -O ^has_journal /dev/vg03/lv01 resize2fs -p /dev/vg03/lv01 dumpe2fs /dev/vg03/lv01 Block count: 1831418880<br /> Block size: 4096<br /> mount -o ro,noatime /dev/vg03/lv01 /mnt/raid OK... but files have been damaged / gone missing.

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• volume group disappeared after xfs_check run

  - by John P

  EDIT** I have a volume group consisting of 5 RAID1 devices grouped together into a lvm and formatted with xfs. The 5th RAID device lost its RAID config (cat /proc/mdstat does not show anything). The two drives are still present (sdj and sdk), but they have no partitions. The LVM appeared to be happily using sdj up until recently. (doing a pvscan showed the first 4 RAID1 devices + /dev/sdj) I removed the LVM from the fstab, rebooted, then ran xfs_check on the LV. It ran for about half an hour, then stopped with an error. I tried rebooting again, and this time when it came up, the logical volume was no longer there. It is now looking for /dev/md5, which is gone (though it had been using /dev/sdj earlier). /dev/sdj was having read errors, but after replacing the SATA cable, those went away, so the drive appears to be fine for now. Can I modify the /etc/lvm/backup/dedvol, change the device to /dev/sdj and do a vgcfgrestore? I could try doing a pvcreate --uuid KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ /dev/sdj to make it recognize it, but I'm afraid that would erase the data on the drive UPDATE: just changing the pv to point to /dev/sdj did not work vgcfgrestore --file /etc/lvm/backup/dedvol dedvol Couldn't find device with uuid 'KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ'. Cannot restore Volume Group dedvol with 1 PVs marked as missing. Restore failed. pvscan /dev/sdj: read failed after 0 of 4096 at 0: Input/output error Couldn't find device with uuid 'KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ'. Couldn't find device with uuid 'KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ'. Couldn't find device with uuid 'KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ'. Couldn't find device with uuid 'KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ'. PV /dev/sdd2 VG VolGroup00 lvm2 [74.41 GB / 0 free] PV /dev/md2 VG dedvol lvm2 [931.51 GB / 0 free] PV /dev/md3 VG dedvol lvm2 [931.51 GB / 0 free] PV /dev/md0 VG dedvol lvm2 [931.51 GB / 0 free] PV /dev/md4 VG dedvol lvm2 [931.51 GB / 0 free] PV unknown device VG dedvol lvm2 [1.82 TB / 63.05 GB free] Total: 6 [5.53 TB] / in use: 6 [5.53 TB] / in no VG: 0 [0 ] vgscan Reading all physical volumes. This may take a while... /dev/sdj: read failed after 0 of 4096 at 0: Input/output error /dev/sdj: read failed after 0 of 4096 at 2000398843904: Input/output error Found volume group "VolGroup00" using metadata type lvm2 Found volume group "dedvol" using metadata type lvm2 vgdisplay dedvol --- Volume group --- VG Name dedvol System ID Format lvm2 Metadata Areas 5 Metadata Sequence No 10 VG Access read/write VG Status resizable MAX LV 0 Cur LV 1 Open LV 0 Max PV 0 Cur PV 5 Act PV 5 VG Size 5.46 TB PE Size 4.00 MB Total PE 1430796 Alloc PE / Size 1414656 / 5.40 TB Free PE / Size 16140 / 63.05 GB VG UUID o1U6Ll-5WH8-Pv7Z-Rtc4-1qYp-oiWA-cPD246 dedvol { id = "o1U6Ll-5WH8-Pv7Z-Rtc4-1qYp-oiWA-cPD246" seqno = 10 status = ["RESIZEABLE", "READ", "WRITE"] flags = [] extent_size = 8192 # 4 Megabytes max_lv = 0 max_pv = 0 physical_volumes { pv0 { id = "Msiee7-Zovu-VSJ3-Y2hR-uBVd-6PaT-Ho9v95" device = "/dev/md2" # Hint only status = ["ALLOCATABLE"] flags = [] dev_size = 1953519872 # 931.511 Gigabytes pe_start = 384 pe_count = 238466 # 931.508 Gigabytes } pv1 { id = "ZittCN-0x6L-cOsW-v1v4-atVN-fEWF-e3lqUe" device = "/dev/md3" # Hint only status = ["ALLOCATABLE"] flags = [] dev_size = 1953519872 # 931.511 Gigabytes pe_start = 384 pe_count = 238466 # 931.508 Gigabytes } pv2 { id = "NRNo0w-kgGr-dUxA-mWnl-bU5v-Wld0-XeKVLD" device = "/dev/md0" # Hint only status = ["ALLOCATABLE"] flags = [] dev_size = 1953519872 # 931.511 Gigabytes pe_start = 384 pe_count = 238466 # 931.508 Gigabytes } pv3 { id = "2EfLFr-JcRe-MusW-mfAs-WCct-u4iV-W0pmG3" device = "/dev/md4" # Hint only status = ["ALLOCATABLE"] flags = [] dev_size = 1953519872 # 931.511 Gigabytes pe_start = 384 pe_count = 238466 # 931.508 Gigabytes } pv4 { id = "KZron2-pPTr-ZYeQ-PKXX-4Woq-6aNc-AG4rRJ" device = "/dev/md5" # Hint only status = ["ALLOCATABLE"] flags = [] dev_size = 3907028992 # 1.81935 Terabytes pe_start = 384 pe_count = 476932 # 1.81935 Terabytes } }

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• How do you re-mount an ext3 fs readwrite after it gets mounted readonly from a disk error?

  - by cagenut

  Its a relatively common problem when something goes wrong in a SAN for ext3 to detect the disk write errors and remount the filesystem read-only. Thats all well and good, only when the SAN is fixed I can't figure out how to re-re-mount the filesystem read-write without rebooting. Behold: [root@localhost ~]# multipath -ll mpath0 (36001f93000a310000299000200000000) dm-2 XIOTECH,ISE1400 [size=1.1T][features=1 queue_if_no_path][hwhandler=0][rw] \_ round-robin 0 [prio=2][active] \_ 1:0:0:1 sdb 8:16 [active][ready] \_ 2:0:0:1 sdc 8:32 [active][ready] [root@localhost ~]# mount /dev/mapper/mpath0 /mnt/foo [root@localhost ~]# touch /mnt/foo/blah All good, now I yank the LUN out from under it. [root@localhost ~]# touch /mnt/foo/blah [root@localhost ~]# touch /mnt/foo/blah touch: cannot touch `/mnt/foo/blah': Read-only file system [root@localhost ~]# tail /var/log/messages Mar 18 13:17:33 localhost multipathd: sdb: tur checker reports path is down Mar 18 13:17:34 localhost multipathd: sdc: tur checker reports path is down Mar 18 13:17:35 localhost kernel: Aborting journal on device dm-2. Mar 18 13:17:35 localhost kernel: Buffer I/O error on device dm-2, logical block 1545 Mar 18 13:17:35 localhost kernel: lost page write due to I/O error on dm-2 Mar 18 13:17:36 localhost kernel: ext3_abort called. Mar 18 13:17:36 localhost kernel: EXT3-fs error (device dm-2): ext3_journal_start_sb: Detected aborted journal Mar 18 13:17:36 localhost kernel: Remounting filesystem read-only It only thinks its read-only, in reality its not even there. [root@localhost ~]# multipath -ll sdb: checker msg is "tur checker reports path is down" sdc: checker msg is "tur checker reports path is down" mpath0 (36001f93000a310000299000200000000) dm-2 XIOTECH,ISE1400 [size=1.1T][features=0][hwhandler=0][rw] \_ round-robin 0 [prio=0][enabled] \_ 1:0:0:1 sdb 8:16 [failed][faulty] \_ 2:0:0:1 sdc 8:32 [failed][faulty] [root@localhost ~]# ll /mnt/foo/ ls: reading directory /mnt/foo/: Input/output error total 20 -rw-r--r-- 1 root root 0 Mar 18 13:11 bar How it still remembers that 'bar' file being there... mystery, but not important right now. Now I re-present the LUN: [root@localhost ~]# tail /var/log/messages Mar 18 13:23:58 localhost multipathd: sdb: tur checker reports path is up Mar 18 13:23:58 localhost multipathd: 8:16: reinstated Mar 18 13:23:58 localhost multipathd: mpath0: queue_if_no_path enabled Mar 18 13:23:58 localhost multipathd: mpath0: Recovered to normal mode Mar 18 13:23:58 localhost multipathd: mpath0: remaining active paths: 1 Mar 18 13:23:58 localhost multipathd: dm-2: add map (uevent) Mar 18 13:23:58 localhost multipathd: dm-2: devmap already registered Mar 18 13:23:59 localhost multipathd: sdc: tur checker reports path is up Mar 18 13:23:59 localhost multipathd: 8:32: reinstated Mar 18 13:23:59 localhost multipathd: mpath0: remaining active paths: 2 Mar 18 13:23:59 localhost multipathd: dm-2: add map (uevent) Mar 18 13:23:59 localhost multipathd: dm-2: devmap already registered [root@localhost ~]# multipath -ll mpath0 (36001f93000a310000299000200000000) dm-2 XIOTECH,ISE1400 [size=1.1T][features=1 queue_if_no_path][hwhandler=0][rw] \_ round-robin 0 [prio=2][enabled] \_ 1:0:0:1 sdb 8:16 [active][ready] \_ 2:0:0:1 sdc 8:32 [active][ready] Great right? It says [rw] right there. Not so fast: [root@localhost ~]# touch /mnt/foo/blah touch: cannot touch `/mnt/foo/blah': Read-only file system OK, doesn't do it automatically, I'll just give it a little push: [root@localhost ~]# mount -o remount /mnt/foo mount: block device /dev/mapper/mpath0 is write-protected, mounting read-only The hell you are: [root@localhost ~]# mount -o remount,rw /mnt/foo mount: block device /dev/mapper/mpath0 is write-protected, mounting read-only Noooooooooo. I have tried all sorts of different mount/tune2fs/dmsetup commands and I cannot figure out how to get it to un-flag the block device as write-protected. Rebooting will fix it, but I'd much rather do it on-line. An hour of googling has gotten me nowhere either. Save me ServerFault.

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• Is this valid JFS partition?

  - by Coolmax

  This is my first question on StackExchange. My teacher gave my his laptop (with Fedora 16 on it) and compact flash card with data. He want to have access to files on card, but he couldn't get access to it. The problem is Linux don't know what type of partion is. I suppose there is JFS: root@debian:~# dmesg |grep sdc [ 9066.908223] sd 3:0:0:1: [sdc] 3940272 512-byte logical blocks: (2.01 GB/1.87 GiB) [ 9066.962307] sd 3:0:0:1: [sdc] Write Protect is off [ 9066.962310] sd 3:0:0:1: [sdc] Mode Sense: 03 00 00 00 [ 9066.962312] sd 3:0:0:1: [sdc] Assuming drive cache: write through [ 9067.028420] sd 3:0:0:1: [sdc] Assuming drive cache: write through [ 9067.028637] sdc: unknown partition table [ 9067.097065] sd 3:0:0:1: [sdc] Assuming drive cache: write through [ 9067.097281] sd 3:0:0:1: [sdc] Attached SCSI removable disk and some of data: root@debian:~# hexdump -Cn 65536 /dev/sdc 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00008000 4a 46 53 31 01 00 00 00 48 63 0e 00 00 00 00 00 |JFS1....Hc......| 00008010 00 10 00 00 0c 00 03 00 00 02 00 00 09 00 00 00 |................| 00008020 00 20 00 00 00 09 20 10 02 00 00 00 00 00 00 00 |. .... .........| 00008030 04 00 00 00 26 00 00 00 02 00 00 00 24 00 00 00 |....&.......$...| 00008040 41 03 00 00 16 00 00 00 00 02 00 00 a0 cc 01 00 |A...............| 00008050 37 00 00 00 69 cc 01 00 b6 d8 ac 4b 00 00 00 00 |7...i......K....| 00008060 32 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 |2...............| 00008070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 00008080 00 00 00 00 00 00 00 00 90 15 e5 5f e3 c4 45 fa |..........._..E.| 00008090 9d 6a 5c b5 4f da 62 1a 00 00 00 00 00 00 00 00 |.j\.O.b.........| 000080a0 00 00 00 00 00 00 00 00 c3 c9 01 00 ed 81 00 00 |................| 000080b0 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 000080c0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * [cut] * 0000f000 4a 46 53 31 01 00 00 00 48 63 0e 00 00 00 00 00 |JFS1....Hc......| 0000f010 00 10 00 00 0c 00 03 00 00 02 00 00 09 00 00 00 |................| 0000f020 00 20 00 00 00 09 20 10 00 00 00 00 00 00 00 00 |. .... .........| 0000f030 04 00 00 00 26 00 00 00 02 00 00 00 24 00 00 00 |....&.......$...| 0000f040 41 03 00 00 16 00 00 00 00 02 00 00 a0 cc 01 00 |A...............| 0000f050 37 00 00 00 69 cc 01 00 b6 d8 ac 4b 00 00 00 00 |7...i......K....| 0000f060 32 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 |2...............| 0000f070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 0000f080 00 00 00 00 00 00 00 00 90 15 e5 5f e3 c4 45 fa |..........._..E.| 0000f090 9d 6a 5c b5 4f da 62 1a 00 00 00 00 00 00 00 00 |.j\.O.b.........| 0000f0a0 00 00 00 00 00 00 00 00 c3 c9 01 00 ed 81 00 00 |................| 0000f0b0 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| 0000f0c0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00010000 I'm total newbie to filesystems. I googled and found that JFS superblock may starts on 0x8000 offset. But what next? How to mount this card? If there would be normal partition table I would expect 55 AA on 510th and 511th byte, but first 8000 bytes are clear. Any help would be greatly appreciated. And sorry for my bad english :) Kind regards.

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• Print directly to CUPS server from non-local clients (Ubuntu 14.04)

  - by OEP

  I set up a CUPS server with a few queues and printing from local clients (the CUPS test page and Samba) seems to work just fine. It seems like the CUPS server is denying non-local clients though: 130.127.48.70 - - [03/Jun/2014:14:29:19 -0400] "POST /printers/m137 HTTP/1.1" 200 390 Validate-Job successful-ok 130.127.48.70 - - [03/Jun/2014:14:29:19 -0400] "POST /printers/m137 HTTP/1.1" 200 339 Create-Job client-error-not-authorized localhost - - [03/Jun/2014:14:40:50 -0400] "POST /printers/m137 HTTP/1.1" 200 410869 Print-Job successful-ok This makes me think I have some sort of host-based restriction in my configuration file, but I can't find it. I've even set my default policy to Allow all only to get the same log message. I'm working from a configuration file which had previously worked on an older version of CUPS, which looks quite similar to the example cupsd.conf. I could be wrong but it looks like that final <Limit All> block ought to allow the actions the logs complain about. MaxLogSize 2000000000 # Log general information in error_log - change "info" to "debug" for # troubleshooting... LogLevel info #AccessLog syslog #ErrorLog syslog #PageLog syslog # Administrator user group... SystemGroup sys root lp # Only listen for connections from the local machine. Listen 0.0.0.0:631 Listen :::631 Listen /var/run/cups/cups.sock ServerName <snipped> # Show shared printers on the local network. Browsing Off BrowseOrder allow,deny # (Change '@LOCAL' to 'ALL' if using directed broadcasts from another subnet.) BrowseAllow @LOCAL # Default authentication type, when authentication is required... DefaultAuthType Basic # Restrict access to the server... <Location /> Order allow,deny Allow all </Location> # Restrict access to the admin pages... <Location /admin> AuthType Default Require user @SYSTEM Encryption Required Order allow,deny Allow all </Location> # Restrict access to configuration files... <Location /admin/conf> AuthType Default Require user @SYSTEM Encryption Required Order allow,deny Allow all </Location> # Set the default printer/job policies... <Policy default> # Job-related operations must be done by the owner or an administrator... <Limit Send-Document Send-URI Hold-Job Release-Job Restart-Job Purge-Jobs Set-Job-Attributes Create-Job-Subscription Renew-Subscription Cancel-Subscription Get-Notifications Reprocess-Job Cancel-Current-Job Suspend-Current-Job Resume-Job CUPS-Move-Job> Require user @OWNER @SYSTEM Order deny,allow </Limit> # All administration operations require an administrator to authenticate... <Limit CUPS-Add-Modify-Printer CUPS-Delete-Printer CUPS-Add-Modify-Class CUPS-Delete-Class CUPS-Set-Default> AuthType Default Require user @SYSTEM Order deny,allow </Limit> # All printer operations require a printer operator to authenticate... <Limit Pause-Printer Resume-Printer Enable-Printer Disable-Printer Pause-Printer-After-Current-Job Hold-New-Jobs Release-Held-New-Jobs Deactivate-Printer Activate-Printer Restart-Printer Shutdown-Printer Startup-Printer Promote-Job Schedule-Job-After CUPS-Accept-Jobs CUPS-Reject-Jobs> AuthType Default Require user @SYSTEM Order deny,allow </Limit> # Only the owner or an administrator can cancel or authenticate a job... <Limit Cancel-Job CUPS-Authenticate-Job> Require user @OWNER @SYSTEM Order deny,allow </Limit> <Limit All> Order allow,deny </Limit> </Policy>

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• Gaming blew fuse and causes funny smell: how to overcome?

  - by George Tomlinson

  I've been gaming for a while now. When playing certain games this PC goes into overdrive. The fan/fans start/s to sound like a jet engine it/they get/s so busy. Also I have smelt burning when this has happened. The fuse blew on the 4 socket adapter I was using recently. On the following thread someone said this could be due to the PSU not being strong enough to handle the load, in what it seems could be a related issue someone had, although the person who posted this question did say that blowing a fan on their PC stopped it crashing in that case: http://www.tomshardware.co.uk/answers/id-2047543/gtx-650-overheating-issue.html. This is exactly what they said: Your GPU isn't overheating. 70+ before it would shutdown and cause a restart. Make sure your PSU is strong enough to handle your new system at load and possibly run Memtest to check your RAM (although not BSOD'ing and just shutting down points to the PSU). This (the PSU part) makes more sense to me than it being to do with dust etc, since it seems a more plausible explanation of why the fuse blew. The PC has no problems except when playing certain games: i.e. TERA Rising and WoW with add-ons (I think WoW is ok as long as I don't have more than 1 add-on (Healers Have To Die)). I'm just wondering if anyone knows or can suggest what I might be able to do to be able to play these games without this problem occurring. The PC's spec is this: Display: NVIDIA GeForce GTX 650 8GB RAM (6 available) Processor: AMD FX (tm) - 8120 Eight-Core Processor - 3.1 GHz, 4 Cores, 8 Logical Processors I have read on another post that forcing vsync in the Nvidia Control Panel helped with what seems could be a similar problem, so I plan to see if that solves it, God permitting. EDIT: I tried the Vsync thing, and it seems the situation may have improved, although this may be due to something else: i.e. maybe the PC was working harder yesterday, due to just having downloaded a few things or lots of things running. I'm still noticing the funny smell when playing TERA. It's not so much burning: it's more like glue. The smell might have had a burning element to it in the past, but I think it's always had a glue element. EDIT 2: the PSU is an 'ATX Switching Power Supply', Model E-500ATX. Other info it gives on the PSU is 230V, Current 10A and Frequency 50-60Hz. It also has some other info which I can supply if necessary. Putting the PC plug in the wall socket instead of the power strip seems like it might have reduced the load on the PC quite a bit: I think it sounds less stressed. it has been off for a while whilst I took the side panel off though, so I'll wait to see what happens before getting too excited. EDIT 3: hmm. So here's the latest: just playing TERA. The fan's running quite fast again. Hard to tell whether switching to the wall socket has made a difference in terms of strain on the PC: I don't know if one would expect it to. Still seems like it might have helped though. Oh and there didn't seem to be much dust in the PC, although I didn't disconnect any components. I'm still getting the glue type smell. ASIDE: reminds me of someone on a PC near me at the library once who was actually sniffing glue right there in front of everyone while on the PC and he started talking about how he was sniffing glue. lol. That's no joke. EDIT 4: So the questions now are: Question 1: Is the smell something I should sort out? (If so, how might I do this?) Question 2: is it necessary to take any steps to prevent blowing another fuse (and if so which step/s?).

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• Informaton of pendriver with libudv on linux

  - by Catanzaro

  I'm doing a little app in C that read the driver information of my pendrive: Plugged it and typed dmesg: [ 7676.243994] scsi 7:0:0:0: Direct-Access Lexar USB Flash Drive 1100 PQ: 0 ANSI: 0 CCS [ 7676.248359] sd 7:0:0:0: Attached scsi generic sg2 type 0 [ 7676.256733] sd 7:0:0:0: [sdb] 7831552 512-byte logical blocks: (4.00 GB/3.73 GiB) [ 7676.266559] sd 7:0:0:0: [sdb] Write Protect is off [ 7676.266566] sd 7:0:0:0: [sdb] Mode Sense: 43 00 00 00 [ 7676.266569] sd 7:0:0:0: [sdb] Assuming drive cache: write through [ 7676.285373] sd 7:0:0:0: [sdb] Assuming drive cache: write through [ 7676.285383] sdb: sdb1 [ 7676.298661] sd 7:0:0:0: [sdb] Assuming drive cache: write through [ 7676.298667] sd 7:0:0:0: [sdb] Attached SCSI removable disk with "udevadm info -q all -n /dev/sdb" P: /devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host7/target7:0:0/7:0:0:0/block/sdb N: sdb W: 36 S: block/8:16 S: disk/by-id/usb-Lexar_USB_Flash_Drive_AA5OCYQII8PSQXBB-0:0 S: disk/by-path/pci-0000:02:03.0-usb-0:1:1.0-scsi-0:0:0:0 E: UDEV_LOG=3 E: DEVPATH=/devices/pci0000:00/0000:00:11.0/0000:02:03.0/usb1/1-1/1-1:1.0/host7/target7:0:0/7:0:0:0/block/sdb E: MAJOR=8 E: MINOR=16 E: DEVNAME=/dev/sdb E: DEVTYPE=disk E: SUBSYSTEM=block E: ID_VENDOR=Lexar E: ID_VENDOR_ENC=Lexar\x20\x20\x20 E: ID_VENDOR_ID=05dc E: ID_MODEL=USB_Flash_Drive E: ID_MODEL_ENC=USB\x20Flash\x20Drive\x20 E: ID_MODEL_ID=a813 E: ID_REVISION=1100 E: ID_SERIAL=Lexar_USB_Flash_Drive_AA5OCYQII8PSQXBB-0:0 E: ID_SERIAL_SHORT=AA5OCYQII8PSQXBB E: ID_TYPE=disk E: ID_INSTANCE=0:0 E: ID_BUS=usb E: ID_USB_INTERFACES=:080650: E: ID_USB_INTERFACE_NUM=00 E: ID_USB_DRIVER=usb-storage E: ID_PATH=pci-0000:02:03.0-usb-0:1:1.0-scsi-0:0:0:0 E: ID_PART_TABLE_TYPE=dos E: UDISKS_PRESENTATION_NOPOLICY=0 E: UDISKS_PARTITION_TABLE=1 E: UDISKS_PARTITION_TABLE_SCHEME=mbr E: UDISKS_PARTITION_TABLE_COUNT=1 E: DEVLINKS=/dev/block/8:16 /dev/disk/by-id/usb-Lexar_USB_Flash_Drive_AA5OCYQII8PSQXBB-0:0 /dev/disk/by-path/pci-0000:02:03.0-usb-0:1:1.0-scsi-0:0:0:0 and my software is: Codice: Seleziona tutto #include <stdio.h> #include <libudev.h> #include <stdlib.h> #include <locale.h> #include <unistd.h> int main(void) { struct udev_enumerate *enumerate; struct udev_list_entry *devices, *dev_list_entry; struct udev_device *dev; /* Create the udev object */ struct udev *udev = udev_new(); if (!udev) { printf("Can't create udev\n"); exit(0); } enumerate = udev_enumerate_new(udev); udev_enumerate_add_match_subsystem(enumerate, "scsi_generic"); udev_enumerate_scan_devices(enumerate); devices = udev_enumerate_get_list_entry(enumerate); udev_list_entry_foreach(dev_list_entry, devices) { const char *path; /* Get the filename of the /sys entry for the device and create a udev_device object (dev) representing it */ path = udev_list_entry_get_name(dev_list_entry); dev = udev_device_new_from_syspath(udev, path); /* usb_device_get_devnode() returns the path to the device node itself in /dev. */ printf("Device Node Path: %s\n", udev_device_get_devnode(dev)); /* The device pointed to by dev contains information about the hidraw device. In order to get information about the USB device, get the parent device with the subsystem/devtype pair of "usb"/"usb_device". This will be several levels up the tree, but the function will find it.*/ dev = udev_device_get_parent_with_subsystem_devtype( dev, "block", "disk"); if (!dev) { printf("Errore\n"); exit(1); } /* From here, we can call get_sysattr_value() for each file in the device's /sys entry. The strings passed into these functions (idProduct, idVendor, serial, etc.) correspond directly to the files in the directory which represents the USB device. Note that USB strings are Unicode, UCS2 encoded, but the strings returned from udev_device_get_sysattr_value() are UTF-8 encoded. */ printf(" VID/PID: %s %s\n", udev_device_get_sysattr_value(dev,"idVendor"), udev_device_get_sysattr_value(dev, "idProduct")); printf(" %s\n %s\n", udev_device_get_sysattr_value(dev,"manufacturer"), udev_device_get_sysattr_value(dev,"product")); printf(" serial: %s\n", udev_device_get_sysattr_value(dev, "serial")); udev_device_unref(dev); } /* Free the enumerator object */ udev_enumerate_unref(enumerate); udev_unref(udev); return 0; } the problem is that i obtain in output: Device Node Path: /dev/sg0 Errore and dont view information. subsystem and the devtype i think that are inserted well : "block" and "disk". thanks for help. Bye

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• Windows 8 Stuck on Start Screen File Search

  - by baturayd

  I have been searching someone else having the same issue but I couldn't find any. Here is my problem: I'm using Windows 8 Pro with Media Center. File search screen does not close itself after I make a file search within start screen. It stuck on that screen. I can't go back to desktop, therefore, task manager is inaccessible. Only way to get out of it is to sign out. It also looks like non-operational. It doesn't give me any result at all. It's just a blank screen with "Files" title. It used to work perfectly. Things I have done before coming here: Safe mode minimal boot to ensure no other 3rd party software interferes. sfc haven't found any inconsistencies. Search index has been rebuild. Normal boot with all 3rd party services and start-up items disabled. System restore to a date that I know this feature was functional. And by the way, I have installed all updates released so far. I strongly used file search via start menu back in Windows 7. This is an absolute game changer for me. I'm curious what causes this. I'll do a "system refresh" if I can't fix this. I'm working on it, I'll keep this thread updated should I find any fix. First update: I just discovered that file search screen gets stuck if it's invoked by typing query directly in start screen. It doesn't get stuck if it's invoked from win + x menu. I was able to "escape" from stuck screen with invoking it again by win + x menu. After rebuilding search index again, search suggestions started to appear again but still there is no file search functionality. Second update: "Results for" expression appears only for a second near to "Files" title when search is initialized. Third update: As a last resort, I finally tried to do a "System Refresh" which has also failed to refresh by giving an error after waiting almost 20 minutes at 99%. (Seriously?) After cold boot it began to undo changes. After changes were reverted, I boot the machine without doing anything further and bingo! Search began acting normal again. This is a totally weird solution. It obviously fixed certain system files during failed refresh, and kept those changes untouched because they were supposed to be that way at the first place. I'll keep this thread alive should anyone comes with a more logical explanation. Forth update: After a windows update, search functionality again stopped responding. It happened after a system update for the first time. Now I have a pretty good suspicion about system update, though I have no solid proof of its involvement with this problem.

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• From Binary to Data Structures

  - by Cédric Menzi

  Table of Contents Introduction PE file format and COFF header COFF file header BaseCoffReader Byte4ByteCoffReader UnsafeCoffReader ManagedCoffReader Conclusion History This article is also available on CodeProject Introduction Sometimes, you want to parse well-formed binary data and bring it into your objects to do some dirty stuff with it. In the Windows world most data structures are stored in special binary format. Either we call a WinApi function or we want to read from special files like images, spool files, executables or may be the previously announced Outlook Personal Folders File. Most specifications for these files can be found on the MSDN Libarary: Open Specification In my example, we are going to get the COFF (Common Object File Format) file header from a PE (Portable Executable). The exact specification can be found here: PECOFF PE file format and COFF header Before we start we need to know how this file is formatted. The following figure shows an overview of the Microsoft PE executable format. Source: Microsoft Our goal is to get the PE header. As we can see, the image starts with a MS-DOS 2.0 header with is not important for us. From the documentation we can read "...After the MS DOS stub, at the file offset specified at offset 0x3c, is a 4-byte...". With this information we know our reader has to jump to location 0x3c and read the offset to the signature. The signature is always 4 bytes that ensures that the image is a PE file. The signature is: PE\0\0. To prove this we first seek to the offset 0x3c, read if the file consist the signature. So we need to declare some constants, because we do not want magic numbers.   private const int PeSignatureOffsetLocation = 0x3c; private const int PeSignatureSize = 4; private const string PeSignatureContent = "PE";   Then a method for moving the reader to the correct location to read the offset of signature. With this method we always move the underlining Stream of the BinaryReader to the start location of the PE signature.   private void SeekToPeSignature(BinaryReader br) { // seek to the offset for the PE signagure br.BaseStream.Seek(PeSignatureOffsetLocation, SeekOrigin.Begin); // read the offset int offsetToPeSig = br.ReadInt32(); // seek to the start of the PE signature br.BaseStream.Seek(offsetToPeSig, SeekOrigin.Begin); }   Now, we can check if it is a valid PE image by reading of the next 4 byte contains the content PE.   private bool IsValidPeSignature(BinaryReader br) { // read 4 bytes to get the PE signature byte[] peSigBytes = br.ReadBytes(PeSignatureSize); // convert it to a string and trim \0 at the end of the content string peContent = Encoding.Default.GetString(peSigBytes).TrimEnd('\0'); // check if PE is in the content return peContent.Equals(PeSignatureContent); }   With this basic functionality we have a good base reader class to try the different methods of parsing the COFF file header. COFF file header The COFF header has the following structure: Offset Size Field 0 2 Machine 2 2 NumberOfSections 4 4 TimeDateStamp 8 4 PointerToSymbolTable 12 4 NumberOfSymbols 16 2 SizeOfOptionalHeader 18 2 Characteristics If we translate this table to code, we get something like this:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public MachineType Machine; public ushort NumberOfSections; public uint TimeDateStamp; public uint PointerToSymbolTable; public uint NumberOfSymbols; public ushort SizeOfOptionalHeader; public Characteristic Characteristics; } BaseCoffReader All readers do the same thing, so we go to the patterns library in our head and see that Strategy pattern or Template method pattern is sticked out in the bookshelf. I have decided to take the template method pattern in this case, because the Parse() should handle the IO for all implementations and the concrete parsing should done in its derived classes.   public CoffHeader Parse() { using (var br = new BinaryReader(File.Open(_fileName, FileMode.Open, FileAccess.Read, FileShare.Read))) { SeekToPeSignature(br); if (!IsValidPeSignature(br)) { throw new BadImageFormatException(); } return ParseInternal(br); } } protected abstract CoffHeader ParseInternal(BinaryReader br);   First we open the BinaryReader, seek to the PE signature then we check if it contains a valid PE signature and rest is done by the derived implementations. Byte4ByteCoffReader The first solution is using the BinaryReader. It is the general way to get the data. We only need to know which order, which data-type and its size. If we read byte for byte we could comment out the first line in the CoffHeader structure, because we have control about the order of the member assignment.   protected override CoffHeader ParseInternal(BinaryReader br) { CoffHeader coff = new CoffHeader(); coff.Machine = (MachineType)br.ReadInt16(); coff.NumberOfSections = (ushort)br.ReadInt16(); coff.TimeDateStamp = br.ReadUInt32(); coff.PointerToSymbolTable = br.ReadUInt32(); coff.NumberOfSymbols = br.ReadUInt32(); coff.SizeOfOptionalHeader = (ushort)br.ReadInt16(); coff.Characteristics = (Characteristic)br.ReadInt16(); return coff; }   If the structure is as short as the COFF header here and the specification will never changed, there is probably no reason to change the strategy. But if a data-type will be changed, a new member will be added or ordering of member will be changed the maintenance costs of this method are very high. UnsafeCoffReader Another way to bring the data into this structure is using a "magically" unsafe trick. As above, we know the layout and order of the data structure. Now, we need the StructLayout attribute, because we have to ensure that the .NET Runtime allocates the structure in the same order as it is specified in the source code. We also need to enable "Allow unsafe code (/unsafe)" in the project's build properties. Then we need to add the following constructor to the CoffHeader structure.   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { unsafe { fixed (byte* packet = &data[0]) { this = *(CoffHeader*)packet; } } } }   The "magic" trick is in the statement: this = *(CoffHeader*)packet;. What happens here? We have a fixed size of data somewhere in the memory and because a struct in C# is a value-type, the assignment operator = copies the whole data of the structure and not only the reference. To fill the structure with data, we need to pass the data as bytes into the CoffHeader structure. This can be achieved by reading the exact size of the structure from the PE file.   protected override CoffHeader ParseInternal(BinaryReader br) { return new CoffHeader(br.ReadBytes(Marshal.SizeOf(typeof(CoffHeader)))); }   This solution is the fastest way to parse the data and bring it into the structure, but it is unsafe and it could introduce some security and stability risks. ManagedCoffReader In this solution we are using the same approach of the structure assignment as above. But we need to replace the unsafe part in the constructor with the following managed part:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { IntPtr coffPtr = IntPtr.Zero; try { int size = Marshal.SizeOf(typeof(CoffHeader)); coffPtr = Marshal.AllocHGlobal(size); Marshal.Copy(data, 0, coffPtr, size); this = (CoffHeader)Marshal.PtrToStructure(coffPtr, typeof(CoffHeader)); } finally { Marshal.FreeHGlobal(coffPtr); } } }     Conclusion We saw that we can parse well-formed binary data to our data structures using different approaches. The first is probably the clearest way, because we know each member and its size and ordering and we have control about the reading the data for each member. But if add member or the structure is going change by some reason, we need to change the reader. The two other solutions use the approach of the structure assignment. In the unsafe implementation we need to compile the project with the /unsafe option. We increase the performance, but we get some security risks.

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• AutoMapper MappingFunction from Source Type of NameValueCollection

  - by REA_ANDREW

  I have had a situation arise today where I need to construct a complex type from a source of a NameValueCollection.  A little while back I submitted a patch for the Agatha Project to include REST (JSON and XML) support for the service contract.  I realized today that as useful as it is, it did not actually support true REST conformance, as REST should support GET so that you can use JSONP from JavaScript directly meaning you can query cross domain services.  My original implementation for POX and JSON used the POST method and this immediately rules out JSONP as from reading, JSONP only works with GET Requests. This then raised another issue.  The current operation contract of Agatha and one of its main benefits is that you can supply an array of Request objects in a single request, limiting the about of server requests you need to make.  Now, at the present time I am thinking that this will not be the case for the REST imlementation but will yield the benefits of the fact that : The same Request objects can be used for SOAP and RST (POX, JSON) The construct of the JavaScript functions will be simpler and more readable It will enable the use of JSONP for cross domain REST Services The current contract for the Agatha WcfRequestProcessor is at time of writing the following: [ServiceContract] public interface IWcfRequestProcessor { [OperationContract(Name = "ProcessRequests")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] Response[] Process(params Request[] requests); [OperationContract(Name = "ProcessOneWayRequests", IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] void ProcessOneWayRequests(params OneWayRequest[] requests); }   My current proposed solution, and at the very early stages of my concept is as follows: [ServiceContract] public interface IWcfRestJsonRequestProcessor { [OperationContract(Name="process")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] [WebGet(UriTemplate = "process/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] Response[] Process(string name, NameValueCollection parameters); [OperationContract(Name="processoneway",IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [WebGet(UriTemplate = "process-one-way/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] void ProcessOneWayRequests(string name, NameValueCollection parameters); }   Now this part I have not yet implemented, it is the preliminart step which I have developed which will allow me to take the name of the Request Type and the NameValueCollection and construct the complex type which is that of the Request which I can then supply to a nested instance of the original IWcfRequestProcessor  and work as it should normally.  To give an example of some of the urls which you I envisage with this method are: http://www.url.com/service.svc/json/process/getweather/?location=london http://www.url.com/service.svc/json/process/getproductsbycategory/?categoryid=1 http://www.url.om/service.svc/json/process/sayhello/?name=andy Another reason why my direction has gone to a single request for the REST implementation is because of restrictions which are imposed by browsers on the length of the url.  From what I have read this is on average 2000 characters.  I think that this is a very acceptable usage limit in the context of using 1 request, but I do not think this is acceptable for accommodating multiple requests chained together.  I would love to be corrected on that one, I really would but unfortunately from what I have read I have come to the conclusion that this is not the case. The mapping function So, as I say this is just the first pass I have made at this, and I am not overly happy with the try catch for detecting types without default constructors.  I know there is a better way but for the minute, it escapes me.  I would also like to know the correct way for adding mapping functions and not using the anonymous way that I have used.  To achieve this I have used recursion which I am sure is what other mapping function use. As you do have to go as deep as the complex type is. public static object RecurseType(NameValueCollection collection, Type type, string prefix) { try { var returnObject = Activator.CreateInstance(type); foreach (var property in type.GetProperties()) { foreach (var key in collection.AllKeys) { if (String.IsNullOrEmpty(prefix) || key.Length > prefix.Length) { var propertyNameToMatch = String.IsNullOrEmpty(prefix) ? key : key.Substring(property.Name.IndexOf(prefix) + prefix.Length + 1); if (property.Name == propertyNameToMatch) { property.SetValue(returnObject, Convert.ChangeType(collection.Get(key), property.PropertyType), null); } else if(property.GetValue(returnObject,null) == null) { property.SetValue(returnObject, RecurseType(collection, property.PropertyType, String.Concat(prefix, property.PropertyType.Name)), null); } } } } return returnObject; } catch (MissingMethodException) { //Quite a blunt way of dealing with Types without default constructor return null; } }   Another thing is performance, I have not measured this in anyway, it is as I say the first pass, so I hope this can be the start of a more perfected implementation.  I tested this out with a complex type of three levels, there is no intended logical meaning to the properties, they are simply for the purposes of example.  You could call this a spiking session, as from here on in, now I know what I am building I would take a more TDD approach.  OK, purists, why did I not do this from the start, well I didn’t, this was a brain dump and now I know what I am building I can. The console test and how I used with AutoMapper is as follows: static void Main(string[] args) { var collection = new NameValueCollection(); collection.Add("Name", "Andrew Rea"); collection.Add("Number", "1"); collection.Add("AddressLine1", "123 Street"); collection.Add("AddressNumber", "2"); collection.Add("AddressPostCodeCountry", "United Kingdom"); collection.Add("AddressPostCodeNumber", "3"); AutoMapper.Mapper.CreateMap<NameValueCollection, Person>() .ConvertUsing(x => { return(Person) RecurseType(x, typeof(Person), null); }); var person = AutoMapper.Mapper.Map<NameValueCollection, Person>(collection); Console.WriteLine(person.Name); Console.WriteLine(person.Number); Console.WriteLine(person.Address.Line1); Console.WriteLine(person.Address.Number); Console.WriteLine(person.Address.PostCode.Country); Console.WriteLine(person.Address.PostCode.Number); Console.ReadLine(); }   Notice the convention that I am using and that this method requires you do use.  Each property is prefixed with the constructed name of its parents combined.  This is the convention used by AutoMapper and it makes sense. I can also think of other uses for this including using with ASP.NET MVC ModelBinders for creating a complex type from the QueryString which is itself is a NameValueCollection. Hope this is of some help to people and I would welcome any code reviews you could give me. References: Agatha : http://code.google.com/p/agatha-rrsl/ AutoMapper : http://automapper.codeplex.com/   Cheers for now, Andrew   P.S. I will have the proposed solution for a more complete REST implementation for AGATHA very soon. 

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• Parallelism in .NET – Part 6, Declarative Data Parallelism

  - by Reed

  When working with a problem that can be decomposed by data, we have a collection, and some operation being performed upon the collection.  I’ve demonstrated how this can be parallelized using the Task Parallel Library and imperative programming using imperative data parallelism via the Parallel class.  While this provides a huge step forward in terms of power and capabilities, in many cases, special care must still be given for relative common scenarios. C# 3.0 and Visual Basic 9.0 introduced a new, declarative programming model to .NET via the LINQ Project.  When working with collections, we can now write software that describes what we want to occur without having to explicitly state how the program should accomplish the task.  By taking advantage of LINQ, many operations become much shorter, more elegant, and easier to understand and maintain.  Version 4.0 of the .NET framework extends this concept into the parallel computation space by introducing Parallel LINQ. Before we delve into PLINQ, let’s begin with a short discussion of LINQ.  LINQ, the extensions to the .NET Framework which implement language integrated query, set, and transform operations, is implemented in many flavors.  For our purposes, we are interested in LINQ to Objects.  When dealing with parallelizing a routine, we typically are dealing with in-memory data storage.  More data-access oriented LINQ variants, such as LINQ to SQL and LINQ to Entities in the Entity Framework fall outside of our concern, since the parallelism there is the concern of the data base engine processing the query itself. LINQ (LINQ to Objects in particular) works by implementing a series of extension methods, most of which work on IEnumerable<T>.  The language enhancements use these extension methods to create a very concise, readable alternative to using traditional foreach statement.  For example, let’s revisit our minimum aggregation routine we wrote in Part 4: double min = double.MaxValue; foreach(var item in collection) { double value = item.PerformComputation(); min = System.Math.Min(min, value); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here, we’re doing a very simple computation, but writing this in an imperative style.  This can be loosely translated to English as: Create a very large number, and save it in min Loop through each item in the collection. For every item: Perform some computation, and save the result If the computation is less than min, set min to the computation Although this is fairly easy to follow, it’s quite a few lines of code, and it requires us to read through the code, step by step, line by line, in order to understand the intention of the developer. We can rework this same statement, using LINQ: double min = collection.Min(item => item.PerformComputation()); Here, we’re after the same information.  However, this is written using a declarative programming style.  When we see this code, we’d naturally translate this to English as: Save the Min value of collection, determined via calling item.PerformComputation() That’s it – instead of multiple logical steps, we have one single, declarative request.  This makes the developer’s intentions very clear, and very easy to follow.  The system is free to implement this using whatever method required. Parallel LINQ (PLINQ) extends LINQ to Objects to support parallel operations.  This is a perfect fit in many cases when you have a problem that can be decomposed by data.  To show this, let’s again refer to our minimum aggregation routine from Part 4, but this time, let’s review our final, parallelized version: // Safe, and fast! double min = double.MaxValue; // Make a "lock" object object syncObject = new object(); Parallel.ForEach( collection, // First, we provide a local state initialization delegate. () => double.MaxValue, // Next, we supply the body, which takes the original item, loop state, // and local state, and returns a new local state (item, loopState, localState) => { double value = item.PerformComputation(); return System.Math.Min(localState, value); }, // Finally, we provide an Action<TLocal>, to "merge" results together localState => { // This requires locking, but it's only once per used thread lock(syncObj) min = System.Math.Min(min, localState); } ); Here, we’re doing the same computation as above, but fully parallelized.  Describing this in English becomes quite a feat: Create a very large number, and save it in min Create a temporary object we can use for locking Call Parallel.ForEach, specifying three delegates For the first delegate: Initialize a local variable to hold the local state to a very large number For the second delegate: For each item in the collection, perform some computation, save the result If the result is less than our local state, save the result in local state For the final delegate: Take a lock on our temporary object to protect our min variable Save the min of our min and local state variables Although this solves our problem, and does it in a very efficient way, we’ve created a set of code that is quite a bit more difficult to understand and maintain. PLINQ provides us with a very nice alternative.  In order to use PLINQ, we need to learn one new extension method that works on IEnumerable<T> – ParallelEnumerable.AsParallel(). That’s all we need to learn in order to use PLINQ: one single method.  We can write our minimum aggregation in PLINQ very simply: double min = collection.AsParallel().Min(item => item.PerformComputation()); By simply adding “.AsParallel()” to our LINQ to Objects query, we converted this to using PLINQ and running this computation in parallel!  This can be loosely translated into English easily, as well: Process the collection in parallel Get the Minimum value, determined by calling PerformComputation on each item Here, our intention is very clear and easy to understand.  We just want to perform the same operation we did in serial, but run it “as parallel”.  PLINQ completely extends LINQ to Objects: the entire functionality of LINQ to Objects is available.  By simply adding a call to AsParallel(), we can specify that a collection should be processed in parallel.  This is simple, safe, and incredibly useful.

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• BNF – how to read syntax?

  - by Piotr Rodak

  A few days ago I read post of Jen McCown (blog) about her idea of blogging about random articles from Books Online. I think this is a great idea, even if Jen says that it’s not exciting or sexy. I noticed that many of the questions that appear on forums and other media arise from pure fact that people asking questions didn’t bother to read and understand the manual – Books Online. Jen came up with a brilliant, concise acronym that describes very well the category of posts about Books Online – RTFM365. I take liberty of tagging this post with the same acronym. I often come across questions of type – ‘Hey, i am trying to create a table, but I am getting an error’. The error often says that the syntax is invalid. 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT DEFAULT Guid_Default NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); 5 The answer is usually(1), ‘Ok, let me check it out.. Ah yes – you have to put name of the DEFAULT constraint before the type of constraint: 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT Guid_Default DEFAULT NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); Why many people stumble on syntax errors? Is the syntax poorly documented? No, the issue is, that correct syntax of the CREATE TABLE statement is documented very well in Books Online and is.. intimidating. Many people can be taken aback by the rather complex block of code that describes all intricacies of the statement. However, I don’t know better way of defining syntax of the statement or command. The notation that is used to describe syntax in Books Online is a form of Backus-Naur notatiion, called BNF for short sometimes. This is a notation that was invented around 50 years ago, and some say that even earlier, around 400 BC – would you believe? Originally it was used to define syntax of, rather ancient now, ALGOL programming language (in 1950’s, not in ancient India). If you look closer at the definition of the BNF, it turns out that the principles of this syntax are pretty simple. Here are a few bullet points: italic_text is a placeholder for your identifier <italic_text_in_angle_brackets> is a definition which is described further. [everything in square brackets] is optional {everything in curly brackets} is obligatory everything | separated | by | operator is an alternative ::= “assigns” definition to an identifier Yes, it looks like these six simple points give you the key to understand even the most complicated syntax definitions in Books Online. Books Online contain an article about syntax conventions – have you ever read it? Let’s have a look at fragment of the CREATE TABLE statement: 1 CREATE TABLE 2 [ database_name . [ schema_name ] . | schema_name . ] table_name 3 ( { <column_definition> | <computed_column_definition> 4 | <column_set_definition> } 5 [ <table_constraint> ] [ ,...n ] ) 6 [ ON { partition_scheme_name ( partition_column_name ) | filegroup 7 | "default" } ] 8 [ { TEXTIMAGE_ON { filegroup | "default" } ] 9 [ FILESTREAM_ON { partition_scheme_name | filegroup 10 | "default" } ] 11 [ WITH ( <table_option> [ ,...n ] ) ] 12 [ ; ] Let’s look at line 2 of the above snippet: This line uses rules 3 and 5 from the list. So you know that you can create table which has specified one of the following. just name – table will be created in default user schema schema name and table name – table will be created in specified schema database name, schema name and table name – table will be created in specified database, in specified schema database name, .., table name – table will be created in specified database, in default schema of the user. Note that this single line of the notation describes each of the naming schemes in deterministic way. The ‘optionality’ of the schema_name element is nested within database_name.. section. You can use either database_name and optional schema name, or just schema name – this is specified by the pipe character ‘|’. The error that user gets with execution of the first script fragment in this post is as follows: Msg 156, Level 15, State 1, Line 2 Incorrect syntax near the keyword 'DEFAULT'. Ok, let’s have a look how to find out the correct syntax. Line number 3 of the BNF fragment above contains reference to <column_definition>. Since column_definition is in angle brackets, we know that this is a reference to notion described further in the code. And indeed, the very next fragment of BNF contains syntax of the column definition. 1 <column_definition> ::= 2 column_name <data_type> 3 [ FILESTREAM ] 4 [ COLLATE collation_name ] 5 [ NULL | NOT NULL ] 6 [ 7 [ CONSTRAINT constraint_name ] DEFAULT constant_expression ] 8 | [ IDENTITY [ ( seed ,increment ) ] [ NOT FOR REPLICATION ] 9 ] 10 [ ROWGUIDCOL ] [ <column_constraint> [ ...n ] ] 11 [ SPARSE ] Look at line 7 in the above fragment. It says, that the column can have a DEFAULT constraint which, if you want to name it, has to be prepended with [CONSTRAINT constraint_name] sequence. The name of the constraint is optional, but I strongly recommend you to make the effort of coming up with some meaningful name yourself. So the correct syntax of the CREATE TABLE statement from the beginning of the article is like this: 1 CREATE TABLE dbo.Employees 2 (guid uniqueidentifier CONSTRAINT Guid_Default DEFAULT NEWSEQUENTIALID() ROWGUIDCOL, 3 Employee_Name varchar(60) 4 CONSTRAINT Guid_PK PRIMARY KEY (guid) ); That is practically everything you should know about BNF. I encourage you to study the syntax definitions for various statements and commands in Books Online, you can find really interesting things hidden there. Technorati Tags: SQL Server,t-sql,BNF,syntax   (1) No, my answer usually is a question – ‘What error message? What does it say?’. You’d be surprised to know how many people think I can go through time and space and look at their screen at the moment they received the error.

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• ODI 12c - Parallel Table Load

  - by David Allan

  In this post we will look at the ODI 12c capability of parallel table load from the aspect of the mapping developer and the knowledge module developer - two quite different viewpoints. This is about parallel table loading which isn't to be confused with loading multiple targets per se. It supports the ability for ODI mappings to be executed concurrently especially if there is an overlap of the datastores that they access, so any temporary resources created may be uniquely constructed by ODI. Temporary objects can be anything basically - common examples are staging tables, indexes, views, directories - anything in the ETL to help the data integration flow do its job. In ODI 11g users found a few workarounds (such as changing the technology prefixes - see here) to build unique temporary names but it was more of a challenge in error cases. ODI 12c mappings by default operate exactly as they did in ODI 11g with respect to these temporary names (this is also true for upgraded interfaces and scenarios) but can be configured to support the uniqueness capabilities. We will look at this feature from two aspects; that of a mapping developer and that of a developer (of procedures or KMs). 1. Firstly as a Mapping Developer..... 1.1 Control when uniqueness is enabled A new property is available to set unique name generation on/off. When unique names have been enabled for a mapping, all temporary names used by the collection and integration objects will be generated using unique names. This property is presented as a check-box in the Property Inspector for a deployment specification. 1.2 Handle cleanup after successful execution Provided that all temporary objects that are created have a corresponding drop statement then all of the temporary objects should be removed during a successful execution. This should be the case with the KMs developed by Oracle. 1.3 Handle cleanup after unsuccessful execution If an execution failed in ODI 11g then temporary tables would have been left around and cleaned up in the subsequent run. In ODI 12c, KM tasks can now have a cleanup-type task which is executed even after a failure in the main tasks. These cleanup tasks will be executed even on failure if the property 'Remove Temporary Objects on Error' is set. If the agent was to crash and not be able to execute this task, then there is an ODI tool (OdiRemoveTemporaryObjects here) you can invoke to cleanup the tables - it supports date ranges and the like. That's all there is to it from the aspect of the mapping developer it's much, much simpler and straightforward. You can now execute the same mapping concurrently or execute many mappings using the same resource concurrently without worrying about conflict.  2. Secondly as a Procedure or KM Developer..... In the ODI Operator the executed code shows the actual name that is generated - you can also see the runtime code prior to execution (introduced in 11.1.1.7), for example below in the code type I selected 'Pre-executed Code' this lets you see the code about to be processed and you can also see the executed code (which is the default view). References to the collection (C$) and integration (I$) names will be automatically made unique by using the odiRef APIs - these objects will have unique names whenever concurrency has been enabled for a particular mapping deployment specification. It's also possible to use name uniqueness functions in procedures and your own KMs. 2.1 New uniqueness tags  You can also make your own temporary objects have unique names by explicitly including either %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG in the name passed to calls to the odiRef APIs. Such names would always include the unique tag regardless of the concurrency setting. To illustrate, let's look at the getObjectName() method. At <% expansion time, this API will append %UNIQUE_STEP_TAG to the object name for collection and integration tables. The name parameter passed to this API may contain  %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. This API always generates to the <? version of getObjectName() At execution time this API will replace the unique tag macros with a string that is unique to the current execution scope. The returned name will conform to the name-length restriction for the target technology, and its pattern for the unique tag. Any necessary truncation will be performed against the initial name for the object and any other fixed text that may have been specified. Examples are:- <?=odiRef.getObjectName("L", "%COL_PRFEMP%UNIQUE_STEP_TAG", "D")?> SCOTT.C$_EABH7QI1BR1EQI3M76PG9SIMBQQ <?=odiRef.getObjectName("L", "EMP%UNIQUE_STEP_TAG_AE", "D")?> SCOTT.EMPAO96Q2JEKO0FTHQP77TMSAIOSR_ Methods which have this kind of support include getFrom, getTableName, getTable, getObjectShortName and getTemporaryIndex. There are APIs for retrieving this tag info also, the getInfo API has been extended with the following properties (the UNIQUE* properties can also be used in ODI procedures); UNIQUE_STEP_TAG - Returns the unique value for the current step scope, e.g. 5rvmd8hOIy7OU2o1FhsF61 Note that this will be a different value for each loop-iteration when the step is in a loop. UNIQUE_SESSION_TAG - Returns the unique value for the current session scope, e.g. 6N38vXLrgjwUwT5MseHHY9 IS_CONCURRENT - Returns info about the current mapping, will return 0 or 1 (only in % phase) GUID_SRC_SET - Returns the UUID for the current source set/execution unit (only in % phase) The getPop API has been extended with the IS_CONCURRENT property which returns info about an mapping, will return 0 or 1.  2.2 Additional APIs Some new APIs are provided including getFormattedName which will allow KM developers to construct a name from fixed-text or ODI symbols that can be optionally truncate to a max length and use a specific encoding for the unique tag. It has syntax getFormattedName(String pName[, String pTechnologyCode]) This API is available at both the % and the ? phase.  The format string can contain the ODI prefixes that are available for getObjectName(), e.g. %INT_PRF, %COL_PRF, %ERR_PRF, %IDX_PRF alongwith %UNIQUE_STEP_TAG or %UNIQUE_SESSION_TAG. The latter tags will be expanded into a unique string according to the specified technology. Calls to this API within the same execution context are guaranteed to return the same unique name provided that the same parameters are passed to the call. e.g. <%=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")%> <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG_AE", "ORACLE")?> C$_MY_TAB7wDiBe80vBog1auacS1xB_AE <?=odiRef.getFormattedName("%COL_PRFMY_TABLE%UNIQUE_STEP_TAG.log", "FILE")?> C2_MY_TAB7wDiBe80vBog1auacS1xB.log 2.3 Name length generation  As part of name generation, the length of the generated name will be compared with the maximum length for the target technology and truncation may need to be applied. When a unique tag is included in the generated string it is important that uniqueness is not compromised by truncation of the unique tag. When a unique tag is NOT part of the generated name, the name will be truncated by removing characters from the end - this is the existing 11g algorithm. When a unique tag is included, the algorithm will first truncate the <postfix> and if necessary  the <prefix>. It is recommended that users will ensure there is sufficient uniqueness in the <prefix> section to ensure uniqueness of the final resultant name. SUMMARY To summarize, ODI 12c make it much simpler to utilize mappings in concurrent cases and provides APIs for helping developing any procedures or custom knowledge modules in such a way they can be used in highly concurrent, parallel scenarios. 

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• Flashing your Windows Phone Dummies

  - by Martin Hinshelwood

  The rate at which vendors release new updates for the HD2 is ridiculously slow. You have to wait for Microsoft to release the new OS, then you wait for HTC to build it into a ROM, and then you have to wait up to 6 months for your operator to badly customise it for their network. Once Windows Phone 7 is released this problem should go away as Microsoft is likely to be able to update the phone over the air, but what do we do until then? I want Windows Mobile 6.5.5 now!   I’m an early adopter. If there is a new version of something then that’s the version I want. As long as you accept that you are using something on a “let the early adopter beware” and accept that there may be bugs, sometimes serious crippling bugs the go for it. Note that I won't be responsible if you end up bricking your phone, unlocking or flashing your radio or ROM can be risky. If you follow the instructions then you should be fine, I've flashed my phones (SPV, M300, M1000, M2000, M3100, TyTN, TyTN 2, HD2) hundreds of times without any problems! I have been using Windows Mobile 6.5.5 before it was called 6.5.5 and for long enough that I don’t even remember when I first started using it. I was using it on my HTC TyTN 2 before I got an HD2 a couple of months before Christmas, and the first custom ROM’s for the HD2 were a couple of months after that. I always update to the latest ROM that I like, and occasionally I go back to the stock ROM’s to have a look see, but I am always disappointed. Terms: Soft Reset: Same as pulling out the battery, but is like a reboot for your phone Hard Reset: Reinstalls the Operating system from the Image that is stored on it ROM: This is Image that is loaded onto your phone and it is used to reinstall your phone whenever you do a “hard reset”. Stock ROM: A ROM from the original vendor… So HTC Cook a ROM: Referring to Cooking a ROM is the process a ROM developer goes through to take all of the parts (OS, Drivers and Applications) that make up a running phone and compiling them into a ROM. ROM Kitchen: A place where you get an SDK and all the component parts of the phone: OD, Drivers and Application. There are usually lots of Tools for making it easier to compile and build the image. Flashing: The process of updating one of the layers of your phone with a new layer Bricked: This is what happens when flashing goes wrong. Your phone is now good for only one thing… stopping paper blowing away in a windy place. You can “cook” you own ROM using one of the many good “ROM Kitchens” or you can use a ROM built and tested by someone else. I have cooked my own ROM before, and while the tutorials are good, it is a lot of hassle. You can only Flash new ROM’s that are specifically for your phone only so find a ROM for your phone and XDA Developers is the best place to look. It has a forum based structure and you can find your phone quite easily. XDA Developer Forum Installing a new ROM does have its risks. In the past there have been stories about phones being “bricked” but I have not heard of a bricked phone for quite some years. if you follow the instructions carefully you should not have any problems. note: Most of the tools are written by people for whom English is not their first language to you will need concentrate hard to understand some of the instructions. Have you ever read a manual that was just literally translated from another language? Enough said… There are a number of layers on your phone that you will need to know about: SPL: This is the lowest level, like a BIOS on a PC and is the Operating Systems gateway to the hardware Radio: I think of this as the hardware drivers, and you will need a different Radio for CDMA than GSM networks ROM: This is like your Windows CD, but it is stored internally to the Phone. Flashing your phone consists of replacing one Image with another and then wiping your phone and automatically reinstall from the Image. Sometimes when you download an Image wither it is for a Radio or for ROM you only get a file called *.nbh. What do you do with this? Well you need an RUU application to push that Image to your phone. The RUU’s are different per phone, but there is a CustomRUU for the HD2 that will update your phone with any *.nbh placed in the same directory. Download and Instructions for CustomRUU #1 Flash HardSPL An SPL is kind of like a BIOS, and the default one has checks to make sure that you are only installing a signed ROM. This would prevent you from installing one that comes from any other source but the vendor. NOTE: Installing a HARD SPL invalidates your warranty so remember to Flash your phone with a “stock” vendor ROM before trying to send your phone in for repairs. Is the warranty reinstated when you go back to a stock ROM? I don’t know… Updating your SPL to a HardSPL effectively unlocks your phone so you can install anything you like. I would recommend the HardSPL2. Download and Instructions for HardSPL2 #2 Task29 One of the problems that has been seen on the HD2 when flashing new ROM’s is that things are left over from the old ROM. For a while the recommendation was to Flash a stock ROM first, but some clever cookies have come up with “Task29” which formats your phone first. After running this your phone will be blank and will only boot to the white HTC logo and no further. You should follow the instructions and reboot (remove battery) and hold down the “volume down” button while turning you HD2 on to enter the bootloader. From here you can run CustomRUU once the USB message appears. Download and Instructions for Task29 #2 Flash Radio You may need to play around with this one, there is no good and bad version and the latest is not always the best. You know that annoying thing when you hit “end call” on your phone and nothing happens? Well that's down to the Radio. Get this version right for you and you may even be able to make calls. From a Windows Mobile as well Download There are no instructions here, but they are the same as th ROM, but you use this *.nbh file. #3 Flash ROM If you have gotten this far then you are probably a pro by now Just download the latest ROM below and Flash to your phone. I have been really impressed by the Artemis line of ROM’s but it is no way the only choice. I like this one as the developer builds them as close to the stock ROM as possible while updating to the latest of everything. Download and Instructions for  Artemis HD2 vXX Conclusion While updating your ROM is not for the faint hearted it provides more options than the Stock ROM’s and quicker feature updates than waiting… Technorati Tags: WM6

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• Company Review: Google Products

  Google, Inc offers an array of products and services to all of its end-users. However their search capabilities are the foundation for Google’s current success and their primary business focus. Currently, Google offers over twenty different search applications that allow users to search the internet for books, maps, videos, images, products and much more. Their product decisions have allowed users demands to be met while focusing on the free based model. This allows users to access Google data free of charge and indirectly gives Google a strong competitive advantage of other competitors along with the accuracy of the search results. According to Google, Inc, they offer the following types of searching capabilities: Alerts Get email updates on the topics of your choice Blog Search Find blogs on your favorite topics  Books Search the full text of books  Custom Search Create a customized search experience for your community  Desktop Search and personalize your computer  Dictionary Search for definitions of words and phrases Directory Search the web, organized by topic or category Earth Explore the world from your computer Finance Business info, news and interactive charts GOOG-411 Find and connect for free with businesses from your phone  Images Search for images on the web Maps View maps and directions News Search thousands of news stories Patent Search Search the full text of US Patents Product Search Search for stuff to buy Scholar Search scholarly papers Toolbar Add a search box to your browser Trends Explore past and present search trends Videos Search for videos on the web Web Search Search billions of web pages Web Search Features Find movies, music, stocks, books and more mapping Google’s free based business model is only one way it differentiates itself from its competition. There is also a strong focus on the accuracy of search results and the speed in which they are returned to the end-user. Quality function deployment (QFD) is a structured method used to help connect user needs to the design features of a project proposed to address those needs. This method is particularly useful in accounting for needs that are not easily articulated or precisely defined according to the U. S. Department of Transportation Federal Highway Administration. Due to the fact that QFD is so customer driven Google is always in a constant state of change in attempt to reengineer its search algorithms, and other dependant systems so that end-users requirements are constantly being met. Value engineering is a key example of this, Google is constantly trying to improve all aspects of its products, improve system maintainability, and system interoperability. Bridgefield Group defines value engineering as an organized methodology that identifies and selects the lowest lifecycle cost options in design, materials and processes that achieves the desired level of performance, reliability and customer satisfaction. In addition, it seeks to remove unnecessary costs in the above areas and is often a joint effort with cross-functional internal teams and relevant suppliers. Common issues that appear when developing large scale systems like Google’s search applications include modular design of a product and/or service and providing accurate value analysis. A design approach that adheres to four fundamental tenets of cohesiveness, encapsulation, self-containment, and high binding to design a system component as an independently operable unit subject to change is how the Open System Joint Task Force defines modular design. More specifically M. S. Schmaltz defines modular software design as having a large collection of statements strung together in one partition of in-line code; we segment or divide the statements into logical groups called modules. Each module performs one or two tasks, and then passes control to another module. By breaking up the code into "bite-sized chunks", so to speak, we are able to better control the flow of data and control. This is especially true in large software systems. Value analysis is a process to evaluate products and services based on effectiveness, safety, and cost. Value analysis involves assessing the quality as well as the cost of a product or service as defined by the Healthcare Financial Management Association.  “Operations Management deals with the design and management of products, processes, services and supply chains. It considers the acquisition, development, and utilization of resources that firms need to deliver the goods and services their clients want.” (MIT,2010) Google, Inc encourages an open environment between all employees, also known as Googlers. This is reinforced by a cross-section team or cross-functional teams comprised from multiple departments assigned to every project so that every department like marketing, finance, and quality assurance has input on every project. In addition, Google is known for their openness to new ideas regardless of the status or seniority of an employee. In fact, Google allows for 20% of an employee’s time can be devoted to developing new ideas and/or pet projects. HumTech.com defines a cross-functional team as a collection of people with varied levels of skills and experience brought together to accomplish a task. As the name implies, Cross-Functional Team members come from different organizational units. Cross-Functional Teams may be permanent or ad hoc. Google’s search application product strategy primarily focuses on mass customization. This is allows Google to create a base search application and allows results to be returned to the end-users quickly based on specific parameters and search settings. In addition, they also store the data that is returned in case other desire the same results based on other end-users supplying the same customized settings. This allows Google to appear to render search results in virtually real-time to the user while allowing for complete customization of the searching criteria. Greg Vogl, a professor at Uganda Martyrs University, defines mass customization as when a business gives its customers the opportunity to tailor its products or services to the customer's specifications. The IT staff at Google play a key role in ensuring that the search application’s product strategy is maintained simply because the IT staff designs, develops, and maintains all of their proprietary applications. In fact, they also maintain all network infrastructure to ensure that it is available to all end-users. References: http://www.google.com/intl/en/options/ http://ops.fhwa.dot.gov/freight/publications/ftat_user_guide/sec5.htm http://www.bridgefieldgroup.com/bridgefieldgroup/glos9.htm#V http://www.acq.osd.mil/osjtf/termsdef.html http://www.cise.ufl.edu/~mssz/Pascal-CGS2462/prog-dsn.html http://www.hfma.org/publications/business_caring_newsletter/exclusives/Supply+and+Inventory+Terms+Defined.htm http://mitsloan.mit.edu/omg/om-definition.php http://www.humtech.com/opm/grtl/ols/ols3.cfm http://www.gregvogl.net/courses/mis1/glossary.htm

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• Is Berkeley DB a NoSQL solution?

  - by Gregory Burd

  Berkeley DB is a library. To use it to store data you must link the library into your application. You can use most programming languages to access the API, the calls across these APIs generally mimic the Berkeley DB C-API which makes perfect sense because Berkeley DB is written in C. The inspiration for Berkeley DB was the DBM library, a part of the earliest versions of UNIX written by AT&T's Ken Thompson in 1979. DBM was a simple key/value hashtable-based storage library. In the early 1990s as BSD UNIX was transitioning from version 4.3 to 4.4 and retrofitting commercial code owned by AT&T with unencumbered code, it was the future founders of Sleepycat Software who wrote libdb (aka Berkeley DB) as the replacement for DBM. The problem it addressed was fast, reliable local key/value storage. At that time databases almost always lived on a single node, even the most sophisticated databases only had simple fail-over two node solutions. If you had a lot of data to store you would choose between the few commercial RDBMS solutions or to write your own custom solution. Berkeley DB took the headache out of the custom approach. These basic market forces inspired other DBM implementations. There was the "New DBM" (ndbm) and the "GNU DBM" (GDBM) and a few others, but the theme was the same. Even today TokyoCabinet calls itself "a modern implementation of DBM" mimicking, and improving on, something first created over thirty years ago. In the mid-1990s, DBM was the name for what you needed if you were looking for fast, reliable local storage. Fast forward to today. What's changed? Systems are connected over fast, very reliable networks. Disks are cheep, fast, and capable of storing huge amounts of data. CPUs continued to follow Moore's Law, processing power that filled a room in 1990 now fits in your pocket. PCs, servers, and other computers proliferated both in business and the personal markets. In addition to the new hardware entire markets, social systems, and new modes of interpersonal communication moved onto the web and started evolving rapidly. These changes cause a massive explosion of data and a need to analyze and understand that data. Taken together this resulted in an entirely different landscape for database storage, new solutions were needed. A number of novel solutions stepped up and eventually a category called NoSQL emerged. The new market forces inspired the CAP theorem and the heated debate of BASE vs. ACID. But in essence this was simply the market looking at what to trade off to meet these new demands. These new database systems shared many qualities in common. There were designed to address massive amounts of data, millions of requests per second, and scale out across multiple systems. The first large-scale and successful solution was Dynamo, Amazon's distributed key/value database. Dynamo essentially took the next logical step and added a twist. Dynamo was to be the database of record, it would be distributed, data would be partitioned across many nodes, and it would tolerate failure by avoiding single points of failure. Amazon did this because they recognized that the majority of the dynamic content they provided to customers visiting their web store front didn't require the services of an RDBMS. The queries were simple, key/value look-ups or simple range queries with only a few queries that required more complex joins. They set about to use relational technology only in places where it was the best solution for the task, places like accounting and order fulfillment, but not in the myriad of other situations. The success of Dynamo, and it's design, inspired the next generation of Non-SQL, distributed database solutions including Cassandra, Riak and Voldemort. The problem their designers set out to solve was, "reliability at massive scale" so the first focal point was distributed database algorithms. Underneath Dynamo there is a local transactional database; either Berkeley DB, Berkeley DB Java Edition, MySQL or an in-memory key/value data structure. Dynamo was an evolution of local key/value storage onto networks. Cassandra, Riak, and Voldemort all faced similar design decisions and one, Voldemort, choose Berkeley DB Java Edition for it's node-local storage. Riak at first was entirely in-memory, but has recently added write-once, append-only log-based on-disk storage similar type of storage as Berkeley DB except that it is based on a hash table which must reside entirely in-memory rather than a btree which can live in-memory or on disk. Berkeley DB evolved too, we added high availability (HA) and a replication manager that makes it easy to setup replica groups. Berkeley DB's replication doesn't partitioned the data, every node keeps an entire copy of the database. For consistency, there is a single node where writes are committed first - a master - then those changes are delivered to the replica nodes as log records. Applications can choose to wait until all nodes are consistent, or fire and forget allowing Berkeley DB to eventually become consistent. Berkeley DB's HA scales-out quite well for read-intensive applications and also effectively eliminates the central point of failure by allowing replica nodes to be elected (using a PAXOS algorithm) to mastership if the master should fail. This implementation covers a wide variety of use cases. MemcacheDB is a server that implements the Memcache network protocol but uses Berkeley DB for storage and HA to replicate the cache state across all the nodes in the cache group. Google Accounts, the user authentication layer for all Google properties, was until recently running Berkeley DB HA. That scaled to a globally distributed system. That said, most NoSQL solutions try to partition (shard) data across nodes in the replication group and some allow writes as well as reads at any node, Berkeley DB HA does not. So, is Berkeley DB a "NoSQL" solution? Not really, but it certainly is a component of many of the existing NoSQL solutions out there. Forgetting all the noise about how NoSQL solutions are complex distributed databases when you boil them down to a single node you still have to store the data to some form of stable local storage. DBMs solved that problem a long time ago. NoSQL has more to do with the layers on top of the DBM; the distributed, sometimes-consistent, partitioned, scale-out storage that manage key/value or document sets and generally have some form of simple HTTP/REST-style network API. Does Berkeley DB do that? Not really. Is Berkeley DB a "NoSQL" solution today? Nope, but it's the most robust solution on which to build such a system. Re-inventing the node-local data storage isn't easy. A lot of people are starting to come to appreciate the sophisticated features found in Berkeley DB, even mimic them in some cases. Could Berkeley DB grow into a NoSQL solution? Absolutely. Our key/value API could be extended over the net using any of a number of existing network protocols such as memcache or HTTP/REST. We could adapt our node-local data partitioning out over replicated nodes. We even have a nice query language and cost-based query optimizer in our BDB XML product that we could reuse were we to build out a document-based NoSQL-style product. XML and JSON are not so different that we couldn't adapt one to work with the other interchangeably. Without too much effort we could add what's missing, we could jump into this No SQL market withing a single product development cycle. Why isn't Berkeley DB already a NoSQL solution? Why aren't we working on it? Why indeed...

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• Developer’s Life – Attitude and Communication – They Can Cause Problems – Notes from the Field #027

  - by Pinal Dave

  [Note from Pinal]: This is a 27th episode of Notes from the Field series. The biggest challenge for anyone is to understand human nature. We human have so many things on our mind at any moment of time. There are cases when what we say is not what we mean and there are cases where what we mean we do not say. We do say and things as per our mood and our agenda in mind. Sometimes there are incidents when our attitude creates confusion in the communication and we end up creating a situation which is absolutely not warranted. In this episode of the Notes from the Field series database expert Mike Walsh explains a very crucial issue we face in our career, which is not technical but more to relate to human nature. Read on this may be the best blog post you might read in recent times. In this week’s note from the field, I’m taking a slight departure from technical knowledge and concepts explained. We’ll be back to it next week, I’m sure. Pinal wanted us to explain some of the issues we bump into and how we see some of our customers arrive at problem situations and how we have helped get them back on the right track. Often it is a technical problem we are officially solving – but in a lot of cases as a consultant, we are really helping fix some communication difficulties. This is a technical blog post and not an “advice column” in a newspaper – but the longer I am a consultant, the more years I add to my experience in technology the more I learn that the vast majority of the problems we encounter have “soft skills” included in the chain of causes for the issue we are helping overcome. This is not going to be exhaustive but I hope that sharing four pieces of advice inspired by real issues starts a process of searching for places where we can be the cause of these challenges and look at fixing them in ourselves. Or perhaps we can begin looking at resolving them in teams that we manage. I’ll share three statements that I’ve either heard, read or said and talk about some of the communication or attitude challenges highlighted by the statement. 1 – “But that’s the SAN Administrator’s responsibility…” I heard that early on in my consulting career when talking with a customer who had serious corruption and no good recent backups – potentially no good backups at all. The statement doesn’t have to be this one exactly, but the attitude here is an attitude of “my job stops here, and I don’t care about the intent or principle of why I’m here.” It’s also a situation of having the attitude that as long as there is someone else to blame, I’m fine…  You see in this case, the DBA had a suspicion that the backups were not being handled right.  They were the DBA and they knew that they had responsibility to ensure SQL backups were good to go – it’s a basic requirement of a production DBA. In my “As A DBA Where Do I start?!” presentation, I argue that is job #1 of a DBA. But in this case, the thought was that there was someone else to blame. Rather than create extra work and take on responsibility it was decided to just let it be another team’s responsibility. This failed the company, the company’s customers and no one won. As technologists – we should strive to go the extra mile. If there is a lack of clarity around roles and responsibilities and we know it – we should push to get it resolved. Especially as the DBAs who should act as the advocates of the data contained in the databases we are responsible for. 2 – “We’ve always done it this way, it’s never caused a problem before!” Complacency. I have to say that many failures I’ve been paid good money to help recover from would have not happened had it been for an attitude of complacency. If any thoughts like this have entered your mind about your situation you may be suffering from it. If, while reading this, you get this sinking feeling in your stomach about that one thing you know should be fixed but haven’t done it.. Why don’t you stop and go fix it then come back.. “We should have better backups, but we’re on a SAN so we should be fine really.” “Technically speaking that could happen, but what are the chances?” “We’ll just clean that up as a fast follow” ..and so on. In the age of tightening IT budgets, increased expectations of up time, availability and performance there is no room for complacency. Our customers and business units expect – no demand – the best. Complacency says “we will give you second best or hopefully good enough and we accept the risk and know this may hurt us later. Sometimes an organization will opt for “good enough” and I agree with the concept that at times the perfect can be the enemy of the good. But when we make those decisions in a vacuum and are not reporting them up and discussing them as an organization that is different. That is us unilaterally choosing to do something less than the best and purposefully playing a game of chance. 3 – “This device must accept interference from other devices but not create any” I’ve paraphrased this one – but it’s something the Federal Communications Commission – a federal agency in the United States that regulates electronic communication – requires of all manufacturers of any device that could cause or receive interference electronically. I blogged in depth about this here (http://www.straightpathsql.com/archives/2011/07/relationship-advice-from-the-fcc/) so I won’t go into much detail other than to say this… If we all operated more on the premise that we should do our best to not be the cause of conflict, and to be less easily offended and less upset when we perceive offense life would be easier in many areas! This doesn’t always cause the issues we are called in to help out. Not directly. But where we see it is in unhealthy relationships between the various technology teams at a client. We’ll see teams hoarding knowledge, not sharing well with others and almost working against other teams instead of working with them. If you trace these problems back far enough it often stems from someone or some group of people violating this principle from the FCC. To Sum It Up Technology problems are easy to solve. At Linchpin People we help many customers get past the toughest technological challenge – and at the end of the day it is really just a repeatable process of pattern based troubleshooting, logical thinking and starting at the beginning and carefully stepping through to the end. It’s easy at the end of the day. The tough part of what we do as consultants is the people skills. Being able to help get teams working together, being able to help teams take responsibility, to improve team to team communication? That is the difficult part, and we get to use the soft skills on every engagement. Work on professional development (http://professionaldevelopment.sqlpass.org/) and see continuing improvement here, not just with technology. I can teach just about anyone how to be an excellent DBA and performance tuner, but some of these soft skills are much more difficult to teach. If you want to get started with performance analytics and triage of virtualized SQL Servers with the help of experts, read more over at Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• A pseudo-listener for AlwaysOn Availability Groups for SQL Server virtual machines running in Azure

  - by MikeD

  I am involved in a project that is implementing SharePoint 2013 on virtual machines hosted in Azure. The back end data tier consists of two Azure VMs running SQL Server 2012, with the SharePoint databases contained in an AlwaysOn Availability Group. I used this "Tutorial: AlwaysOn Availability Groups in Windows Azure (GUI)" to help me implement this setup.Because Azure DHCP will not assign multiple unique IP addresses to the same VM, having an AG Listener in Azure is not currently supported.  I wanted to figure out another mechanism to support a "pseudo listener" of some sort. First, I created a CNAME (alias) record in the DNS zone with a short TTL (time to live) of 5 minutes (I may yet make this even shorter). The record represents a logical name (let's say the alias is SPSQL) of the server to connect to for the databases in the availability group (AG). When Server1 was hosting the primary replica of the AG, I would set the CNAME of SPSQL to be SERVER1. When the AG failed over to Server1, I wanted to set the CNAME to SERVER2. Seemed simple enough.(It's important to point out that the connection strings for my SharePoint services should use the CNAME alias, and not the actual server name. This whole thing falls apart otherwise.)To accomplish this, I created identical SQL Agent Jobs on Server1 and Server2, with two steps:1. Step 1: Determine if this server is hosting the primary replica.This is a TSQL step using this script:declare @agName sysname = 'AGTest'set nocount on declare @primaryReplica sysnameselect @primaryReplica = agState.primary_replicafrom sys.dm_hadr_availability_group_states agState   join sys.availability_groups ag on agstate.group_id = ag.group_id   where ag.name = @AGname if not exists(   select *    from sys.dm_hadr_availability_group_states agState   join sys.availability_groups ag on agstate.group_id = ag.group_id   where @@Servername = agstate.primary_replica    and ag.name = @AGname)begin   raiserror ('Primary replica of %s is not hosted on %s, it is hosted on %s',17,1,@Agname, @@Servername, @primaryReplica) endThis script determines if the primary replica value of the AG group is the same as the server name, which means that our server is hosting the current AG (you should update the value of the @AgName variable to the name of your AG). If this is true, I want the DNS alias to point to this server. If the current server is not hosting the primary replica, then the script raises an error. Also, if the script can't be executed because it cannot connect to the server, that also will generate an error. For the job step settings, I set the On Failure option to "Quit the job reporting success". The next step in the job will set the DNS alias to this server name, and I only want to do that if I know that it is the current primary replica, otherwise I don't want to do anything. I also include the step output in the job history so I can see the error message.Job Step 2: Update the CNAME entry in DNS with this server's name.I used a PowerShell script to accomplish this:$cname = "SPSQL.contoso.com"$query = "Select * from MicrosoftDNS_CNAMEType"$dns1 = "dc01.contoso.com"$dns2 = "dc02.contoso.com"if ((Test-Connection -ComputerName $dns1 -Count 1 -Quiet) -eq $true){    $dnsServer = $dns1}elseif ((Test-Connection -ComputerName $dns2 -Count 1 -Quiet) -eq $true) {   $dnsServer = $dns2}else{  $msg = "Unable to connect to DNS servers: " + $dns1 + ", " + $dns2   Throw $msg}$record = Get-WmiObject -Namespace "root\microsoftdns" -Query $query -ComputerName $dnsServer  | ? { $_.Ownername -match $cname }$thisServer = [System.Net.Dns]::GetHostEntry("LocalHost").HostName + "."$currentServer = $record.RecordData if ($currentServer -eq $thisServer ) {     $cname + " CNAME is up to date: " + $currentServer}else{    $cname + " CNAME is being updated to " + $thisServer + ". It was " + $currentServer    $record.RecordData = $thisServer    $record.put()}This script does a few things:finds a responsive domain controller (Test-Connection does a ping and returns a Boolean value if you specify the -Quiet parameter)makes a WMI call to the domain controller to get the current CNAME record value (Get-WmiObject)gets the FQDN of this server (GetHostEntry)checks if the CNAME record is correct and updates it if necessary(You should update the values of the variables $cname, $dns1 and $dns2 for your environment.)Since my domain controllers are also hosted in Azure VMs, either one of them could be down at any point in time, so I need to find a DC that is responsive before attempting the DNS call. The other little thing here is that the CNAME record contains the FQDN of a machine, plus it ends with a period. So the comparison of the CNAME record has to take the trailing period into account. When I tested this step, I was getting ACCESS DENIED responses from PowerShell for the Get-WmiObject cmdlet that does a remote lookup on the DC. This occurred because the SQL Agent service account was not a member of the Domain Admins group, so I decided to create a SQL Credential to store the credentials for a domain administrator account and use it as a PowerShell proxy (rather than give the service account Domain Admins membership).In SQL Management Studio, right click on the Credentials node (under the server's Security node), and choose New Credential...Then, under SQL Agent-->Proxies, right click on the PowerShell node and choose New Proxy...Finally, in the job step properties for the PowerShell step, select the new proxy in the Run As drop down.I created this two step Job on both nodes of the Availability Group, but if you had more than two nodes, just create the same job on all the servers. I set the schedule for the job to execute every minute.When the server that is hosting the primary replica is running the job, the job history looks like this:The job history on the secondary server looks like this: When a failover occurs, the SQL Agent job on the new primary replica will detect that the CNAME needs to be updated within a minute. Based on the TTL of the CNAME (which I said at the beginning was 5 minutes), the SharePoint servers will get the new alias within five minutes and should be able to reconnect. I may want to shorten up the TTL to reduce the time it takes for the client connections to use the new alias. Using a DNS CNAME and a SQL Agent Job on all servers hosting AG replicas, I was able to create a pseudo-listener to automatically change the name of the server that was hosting the primary replica, for a scenario where I cannot use a regular AG listener (in this case, because the servers are all hosted in Azure).    

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• Visiting the Emtel Data Centre

  Back in February at the first event of the Emtel Knowledge Series (EKS) I spoke to various people at Emtel about their data centre here on the island. I was trying to see whether it would be possible to arrange a meeting over there for a selected group of our community members. Well, let's say it like this... My first approach wasn't that promising and far from successful but during the following months there were more and more occasions to get in touch with the "right" contact persons at Emtel to make it happen... Setting up an appointment and pre-requisites The major improvement came during a Boot Camp for Windows Phone 8.1 App development organised by Microsoft Indian Ocean Islands in cooperation with Emtel at the Emtel World, Ebene. Apart from learning bits and pieces regarding Universal Apps I took the opportunity to get in touch with Arvin Lockee, Sales Executive - Data, during our lunch break. And this really kicked off the whole procedure. Prior to get access to the Emtel data centre it is requested that you provide full name and National ID of anyone going to visit. Also, it should be noted that there was only a limited amount of seats available. Anyways, packed with this information I posted through the usual social media channels. Responses came in very quickly and based on First-come, first-serve (FCFS) principle I noted down the details and forwarded them to Emtel in order to fix a date and time for the visit. In preparation on our side, all attendees exchanged contact details and we organised transport options to go to the data centre in Arsenal. The day before and on the day of our meeting, Arvin send me a reminder to check whether everything is still confirmed and ready to go... Of course, it was! Arriving at the Emtel Data Centre As I'm coming from Flic En Flac towards the North, we agreed that I'm going to pick up a couple of young fellows near the old post office in Port Louis. All went well, except that Sean eventually might be living in another time zone compared to the rest of us. Anyway, after some extended stop we were complete and arrived just in time in Arsenal to meet and greet with Ish and Veer. Again, Emtel is taking access procedures to their data centre very serious and the gate stayed close until all our IDs had been noted and compared to the list of registered attendees. Despite having a good laugh at the mixture of old and new ID cards it was a straight-forward processing. The ward was very helpful and guided us to the waiting area at the entrance section of the building. Shortly after we were welcomed by Kamlesh Bokhoree, the Data Centre Officer. He gave us brief introduction into the rules and regulations during our visit, like no photography allowed, not touching the buttons, and following his instructions through the whole visit. Of course! Inside the data centre Next, he explained us the multi-factor authentication system using a combination of bio-metric data, like finger print reader, and "classic" pin panel. The Emtel data centre provides multiple services and next to co-location for your own hardware they also offer storage options for your backup and archive data in their massive, fire-resistant vault. Very impressive to get to know about the considerations that have been done in choosing the right location and how to set up the whole premises. It should also be noted that there is 24/7 CCTV surveillance inside and outside the buildings. Strengths of the Emtel TIER 3 Data Centre, Mauritius Finally, we were guided into the first server room. And wow, the whole setup is cleverly planned and outlined in the architecture. From the false floor and ceilings in order to provide optimum air flow, over to the separation of cold and hot aisles between the full-size server racks, and of course the monitored air conditions in order to analyse and watch changes in temperature, smoke detection and other parameters. And not surprisingly everything has been implemented in two independent circuits. There is a standardised classification for the construction and operation of data centres world-wide, and the Emtel's one has been designed to be a TIER 4 building but due to the lack of an alternative power supplier on the island it is officially registered as a TIER 3 compliant data centre. Maybe in the long run there might be a second supplier of energy next to CEB... time will tell. Luckily, the data centre is integrated into the National Fibre Optic Gigabit Ring and Emtel already connects internationally through diverse undersea cable routes like SAFE & LION/LION2 out of Mauritius and through several other providers for onwards connectivity. The data centre is part of the National Fibre Optic Gigabit Ring and has redundant internet connectivity onwards. Meanwhile, Arvin managed to join our little group of geeks and he supported Kamlesh in answering our technical questions regarding the capacities and general operation of the data centre. Visiting the NOC and its dedicated team of IT professionals was surely one of the visual highlights. Seeing their wall of screens to monitor any kind of activities on the data lines, the managed servers and the activity in and around the building was great. Even though I'm using a multi-head setup since years I cannot keep it up with that setup... ;-) But I got a couple of ideas on how to improve my work spaces here at the office. Clear advantages of hosting your e-commerce and mobile backends locally After the completely isolated NOC area we continued our Q&A session with Kamlesh and Arvin in the second server room which is dedictated to shared environments. On first thought it should be well-noted that there is lots of space for full-sized racks and therefore co-location of your own hardware. Actually, given the feedback that there will be upcoming changes in prices the facilities at the Emtel data centre are getting more and more competitive and interesting for local companies, especially small and medium enterprises. After seeing this world-class infrastructure available on the island, I'm already considering of moving one of my root servers abroad to be co-located here on the island. This would provide an improved user experience in terms of site performance and latency. This would be a good improvement, especially for upcoming e-commerce solutions for two of my local clients. Later on, we actually started the conversation of additional services that could be a catalyst for the local market in order to attract more small and medium companies to take the data centre into their evaluations regarding online activities. Until today Emtel does not provide virtualised server environments but there might be ongoing plans in the future to cover this field as well. Emtel is a mobile operator and internet connectivity provider in the first place, entering a market of managed and virtualised server infrastructures including capacities in terms of cloud storage and computing are rather new and there is a continuous learning curve at Emtel, too. You cannot just jump into a new market and see how it works out... And I appreciate Emtel's approach towards a solid fundament and then building new services on top of that. Emtel as a future one-stop-shop service provider for all your internet and telecommunications needs. Emtel's promotional video about their TIER 3 data centre in Arsenal, Mauritius More details are thoroughly described in Emtel's brochure of their data centre. Check out their PDF document here. Thanks for this opportunity Visiting and walking through the Emtel data centre for more than 2 hours was a great experience. As representative of the Mauritius Software Craftsmanship Community (MSCC) I would like to thank anyone at Emtel involved in the process of making it happen, and especially to Arvin Lockee and Kamlesh Bokhoree for their time and patience in explaining the infrastructure and answering all the endless questions from our members. Thank You!

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• API Message Localization

  - by Jesse Taber

  In my post, “Keep Localizable Strings Close To Your Users” I talked about the internationalization and localization difficulties that can arise when you sprinkle static localizable strings throughout the different logical layers of an application. The main point of that post is that you should have your localizable strings reside as close to the user-facing modules of your application as possible. For example, if you’re developing an ASP .NET web forms application all of the localizable strings should be kept in .resx files that are associated with the .aspx views of the application. In this post I want to talk about how this same concept can be applied when designing and developing APIs. An API Facilitates Machine-to-Machine Interaction You can typically think about a web, desktop, or mobile application as a collection “views” or “screens” through which users interact with the underlying logic and data. The application can be designed based on the assumption that there will be a human being on the other end of the screen working the controls. You are designing a machine-to-person interaction and the application should be built in a way that facilitates the user’s clear understanding of what is going on. Dates should be be formatted in a way that the user will be familiar with, messages should be presented in the user’s preferred language, etc. When building an API, however, there are no screens and you can’t make assumptions about who or what is on the other end of each call. An API is, by definition, a machine-to-machine interaction. A machine-to-machine interaction should be built in a way that facilitates a clear and unambiguous understanding of what is going on. Dates and numbers should be formatted in predictable and standard ways (e.g. ISO 8601 dates) and messages should be presented in machine-parseable formats. For example, consider an API for a time tracking system that exposes a resource for creating a new time entry. The JSON for creating a new time entry for a user might look like: 1: { 2: "userId": 4532, 3: "startDateUtc": "2012-10-22T14:01:54.98432Z", 4: "endDateUtc": "2012-10-22T11:34:45.29321Z" 5: }   Note how the parameters for start and end date are both expressed as ISO 8601 compliant dates in UTC. Using a date format like this in our API leaves little room for ambiguity. It’s also important to note that using ISO 8601 dates is a much, much saner thing than the \/Date(<milliseconds since epoch>)\/ nonsense that is sometimes used in JSON serialization. Probably the most important thing to note about the JSON snippet above is the fact that the end date comes before the start date! The API should recognize that and disallow the time entry from being created, returning an error to the caller. You might inclined to send a response that looks something like this: 1: { 2: "errors": [ {"message" : "The end date must come after the start date"}] 3: }   While this may seem like an appropriate thing to do there are a few problems with this approach: What if there is a user somewhere on the other end of the API call that doesn’t speak English?  What if the message provided here won’t fit properly within the UI of the application that made the API call? What if the verbiage of the message isn’t consistent with the rest of the application that made the API call? What if there is no user directly on the other end of the API call (e.g. this is a batch job uploading time entries once per night unattended)? The API knows nothing about the context from which the call was made. There are steps you could take to given the API some context (e.g.allow the caller to send along a language code indicating the language that the end user speaks), but that will only get you so far. As the designer of the API you could make some assumptions about how the API will be called, but if we start making assumptions we could very easily make the wrong assumptions. In this situation it’s best to make no assumptions and simply design the API in such a way that the caller has the responsibility to convey error messages in a manner that is appropriate for the context in which the error was raised. You would work around some of these problems by allowing callers to add metadata to each request describing the context from which the call is being made (e.g. accepting a ‘locale’ parameter denoting the desired language), but that will add needless clutter and complexity. It’s better to keep the API simple and push those context-specific concerns down to the caller whenever possible. For our very simple time entry example, this can be done by simply changing our error message response to look like this: 1: { 2: "errors": [ {"code": 100}] 3: }   By changing our error error from exposing a string to a numeric code that is easily parseable by another application, we’ve placed all of the responsibility for conveying the actual meaning of the error message on the caller. It’s best to have the caller be responsible for conveying this meaning because the caller understands the context much better than the API does. Now the caller can see error code 100, know that it means that the end date submitted falls before the start date and take appropriate action. Now all of the problems listed out above are non-issues because the caller can simply translate the error code of ‘100’ into the proper action and message for the current context. The numeric code representation of the error is a much better way to facilitate the machine-to-machine interaction that the API is meant to facilitate. An API Does Have Human Users While APIs should be built for machine-to-machine interaction, people still need to wire these interactions together. As a programmer building a client application that will consume the time entry API I would find it frustrating to have to go dig through the API documentation every time I encounter a new error code (assuming the documentation exists and is accurate). The numeric error code approach hurts the discoverability of the API and makes it painful to integrate with. We can help ease this pain by merging our two approaches: 1: { 2: "errors": [ {"code": 100, "message" : "The end date must come after the start date"}] 3: }   Now we have an easily parseable numeric error code for the machine-to-machine interaction that the API is meant to facilitate and a human-readable message for programmers working with the API. The human-readable message here is not intended to be viewed by end-users of the API and as such is not really a “localizable string” in my opinion. We could opt to expose a locale parameter for all API methods and store translations for all error messages, but that’s a lot of extra effort and overhead that doesn’t add a lot real value to the API. I might be a bit of an “ugly American”, but I think it’s probably fine to have the API return English messages when the target for those messages is a programmer. When resources are limited (which they always are), I’d argue that you’re better off hard-coding these messages in English and putting more effort into building more useful features, improving security, tweaking performance, etc.

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• VS 2010 Debugger Improvements (BreakPoints, DataTips, Import/Export)

  - by ScottGu

  This is the twenty-first in a series of blog posts I’m doing on the VS 2010 and .NET 4 release.  Today’s blog post covers a few of the nice usability improvements coming with the VS 2010 debugger.  The VS 2010 debugger has a ton of great new capabilities.  Features like Intellitrace (aka historical debugging), the new parallel/multithreaded debugging capabilities, and dump debuging support typically get a ton of (well deserved) buzz and attention when people talk about the debugging improvements with this release.  I’ll be doing blog posts in the future that demonstrate how to take advantage of them as well.  With today’s post, though, I thought I’d start off by covering a few small, but nice, debugger usability improvements that were also included with the VS 2010 release, and which I think you’ll find useful. Breakpoint Labels VS 2010 includes new support for better managing debugger breakpoints.  One particularly useful feature is called “Breakpoint Labels” – it enables much better grouping and filtering of breakpoints within a project or across a solution.  With previous releases of Visual Studio you had to manage each debugger breakpoint as a separate item. Managing each breakpoint separately can be a pain with large projects and for cases when you want to maintain “logical groups” of breakpoints that you turn on/off depending on what you are debugging.  Using the new VS 2010 “breakpoint labeling” feature you can now name these “groups” of breakpoints and manage them as a unit. Grouping Multiple Breakpoints Together using a Label Below is a screen-shot of the breakpoints window within Visual Studio 2010.  This lists all of the breakpoints defined within my solution (which in this case is the ASP.NET MVC 2 code base): The first and last breakpoint in the list above breaks into the debugger when a Controller instance is created or released by the ASP.NET MVC Framework. Using VS 2010, I can now select these two breakpoints, right-click, and then select the new “Edit labels…” menu command to give them a common label/name (making them easier to find and manage): Below is the dialog that appears when I select the “Edit labels” command.  We can use it to create a new string label for our breakpoints or select an existing one we have already defined.  In this case we’ll create a new label called “Lifetime Management” to describe what these two breakpoints cover: When we press the OK button our two selected breakpoints will be grouped under the newly created “Lifetime Management” label: Filtering/Sorting Breakpoints by Label We can use the “Search” combobox to quickly filter/sort breakpoints by label.  Below we are only showing those breakpoints with the “Lifetime Management” label: Toggling Breakpoints On/Off by Label We can also toggle sets of breakpoints on/off by label group.  We can simply filter by the label group, do a Ctrl-A to select all the breakpoints, and then enable/disable all of them with a single click: Importing/Exporting Breakpoints VS 2010 now supports importing/exporting breakpoints to XML files – which you can then pass off to another developer, attach to a bug report, or simply re-load later.  To export only a subset of breakpoints, you can filter by a particular label and then click the “Export breakpoint” button in the Breakpoints window: Above I’ve filtered my breakpoint list to only export two particular breakpoints (specific to a bug that I’m chasing down).  I can export these breakpoints to an XML file and then attach it to a bug report or email – which will enable another developer to easily setup the debugger in the correct state to investigate it on a separate machine.  Pinned DataTips Visual Studio 2010 also includes some nice new “DataTip pinning” features that enable you to better see and track variable and expression values when in the debugger.  Simply hover over a variable or expression within the debugger to expose its DataTip (which is a tooltip that displays its value)  – and then click the new “pin” button on it to make the DataTip always visible: You can “pin” any number of DataTips you want onto the screen.  In addition to pinning top-level variables, you can also drill into the sub-properties on variables and pin them as well.  Below I’ve “pinned” three variables: “category”, “Request.RawUrl” and “Request.LogonUserIdentity.Name”.  Note that these last two variable are sub-properties of the “Request” object.   Associating Comments with Pinned DataTips Hovering over a pinned DataTip exposes some additional UI within the debugger: Clicking the comment button at the bottom of this UI expands the DataTip - and allows you to optionally add a comment with it: This makes it really easy to attach and track debugging notes: Pinned DataTips are usable across both Debug Sessions and Visual Studio Sessions Pinned DataTips can be used across multiple debugger sessions.  This means that if you stop the debugger, make a code change, and then recompile and start a new debug session - any pinned DataTips will still be there, along with any comments you associate with them.  Pinned DataTips can also be used across multiple Visual Studio sessions.  This means that if you close your project, shutdown Visual Studio, and then later open the project up again – any pinned DataTips will still be there, along with any comments you associate with them. See the Value from Last Debug Session (Great Code Editor Feature) How many times have you ever stopped the debugger only to go back to your code and say: $#@! – what was the value of that variable again??? One of the nice things about pinned DataTips is that they keep track of their “last value from debug session” – and you can look these values up within the VB/C# code editor even when the debugger is no longer running.  DataTips are by default hidden when you are in the code editor and the debugger isn’t running.  On the left-hand margin of the code editor, though, you’ll find a push-pin for each pinned DataTip that you’ve previously setup: Hovering your mouse over a pinned DataTip will cause it to display on the screen.  Below you can see what happens when I hover over the first pin in the editor - it displays our debug session’s last values for the “Request” object DataTip along with the comment we associated with them: This makes it much easier to keep track of state and conditions as you toggle between code editing mode and debugging mode on your projects. Importing/Exporting Pinned DataTips As I mentioned earlier in this post, pinned DataTips are by default saved across Visual Studio sessions (you don’t need to do anything to enable this). VS 2010 also now supports importing/exporting pinned DataTips to XML files – which you can then pass off to other developers, attach to a bug report, or simply re-load later. Combined with the new support for importing/exporting breakpoints, this makes it much easier for multiple developers to share debugger configurations and collaborate across debug sessions. Summary Visual Studio 2010 includes a bunch of great new debugger features – both big and small.  Today’s post shared some of the nice debugger usability improvements. All of the features above are supported with the Visual Studio 2010 Professional edition (the Pinned DataTip features are also supported in the free Visual Studio 2010 Express Editions)  I’ll be covering some of the “big big” new debugging features like Intellitrace, parallel/multithreaded debugging, and dump file analysis in future blog posts.  Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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• Portal And Content - Content Integration - Best Practices

  - by Stefan Krantz

  Lately we have seen an increase in projects that have failed to either get user friendly content integration or non satisfactory performance. Our intention is to mitigate any knowledge gap that our previous post might have left you with, therefore this post will repeat some recommendation or reference back to old useful post. Moreover this post will help you understand ground up how to design, architect and implement business enabled, responsive and performing portals with complex requirements on business centric information publishing. Design the Information Model The key to successful portal deployments is Information modeling, it's a key task to understand the use case you designing for, therefore I have designed a set of question you need to ask yourself or your customer: Question: Who will own the content, IT or Business? Answer: BusinessQuestion: Who will publish the content, IT or Business? Answer: BusinessQuestion: Will there be multiple publishers? Answer: YesQuestion: Are the publishers computer scientist?Answer: NoQuestion: How often do the information changes, daily, weekly, monthly?Answer: Daily, weekly If your answers to the questions matches at least 2, we strongly recommend you design your content with following principles: Divide your pages in to logical sections, where each section is marked with its purpose Assign capabilities to each section, does it contain text, images, formatting and/or is it static and is populated through other contextual information Select editor/design element type WYSIWYG - Rich Text Plain Text - non-format text Image - Image object Static List - static list of formatted informationDynamic Data List - assembled information from multiple data files through CMIS query The result of such design map could look like following below examples: Based on the outcome of the required elements in the design column 3 from the left you will now simply design a data model in WebCenter Content - Site Studio by creating a Region Definition structure matching your design requirements.For more information on how to create a Region definition see following post: Region Definition Post - note see instruction 7 for details. Each region definition can now be used to instantiate data files, a data file will hold the actual data for each element in the region definition. Another way you can see this is to compare the region definition as an extension to the metadata model in WebCenter Content for each data file item. Design content templates With a solid dependable information model we can now proceed to template creation and page design, in this phase focuses on how to place the content sections from the region definition on the page via a Content Presenter template. Remember by creating content presenter templates you will leverage the latest and most integrated technology WebCenter has to offer. This phase is much easier since the you already have the information model and design wire-frames to base the logic on, however there is still few considerations to pay attention to: Base the template on ADF and make only necessary exceptions to markup when required Leverage ADF design components for Tabs, Accordions and other similar components, this way the design in the content published areas will comply with other design areas based on custom ADF taskflows There is no performance impact when using meta data or region definition based data All data access regardless of type, metadata or xml data it can be accessed via the Content Presenter - Node. See below for applied examples on how to access data Access metadata property from Document - #{node.propertyMap['myProp'].value}myProp in this example can be for instance (dDocName, dDocTitle, xComments or any other available metadata) Access element data from data file xml - #{node.propertyMap['[Region Definition Name]:[Element name]'].asTextHtml}Region Definition Name is the expect region definition that the current data file is instantiatingElement name is the element value you like to grab from the data file I recommend you read following  useful post on content template topic:CMIS queries and template creation - note see instruction 9 for detailsStatic List template rendering For more information on templates:Single Item Content TemplateMulti Item Content TemplateExpression Language Internationalization Considerations When integrating content assets via content presenter you by now probably understand that the content item/data file is wired to the page, what is also pretty common at this stage is that the content item/data file only support one language since its not practical or business friendly to mix that into a complex structure. Therefore you will be left with a very common dilemma that you will have to either build a complete new portal for each locale, which is not an good option! However with little bit of information modeling and clear naming convention this can be addressed. Basically you can simply make sure that all content item/data file are named with a predictable naming convention like "Content1_EN" for the English rendition and "Content1_ES" for the Spanish rendition. This way through simple none complex customizations you will be able to dynamically switch the actual content item/data file just before rendering. By following proposed approach above you not only enable a simple mechanism for internationalized content you also preserve the functionality in the content presenter to support business accessible run-time publishing of information on existing and new pages. I recommend you read following useful post on Internationalization topics:Internationalize with Content Presenter Integrate with Review & Approval processes Today the Review and approval functionality and configuration is based out of WebCenter Content - Criteria Workflows. Criteria Workflows uses the metadata of the checked in document to evaluate if the document is under any review/approval process. So for instance if a Criteria Workflow is configured to force any documents with Version = "2" or "higher" and Content Type is "Instructions", any matching content item version on check in will now enter the workflow before getting released for general access. Few things to consider when configuring Criteria Workflows: Make sure to not trigger on version one for Content Items that are Data Files - if you trigger on version 1 you will not only approve an empty document you will also have a content presenter pointing to a none existing document - since the document will only be available after successful completion of the workflow Approval workflows sometimes requires more complex criteria, the recommendation if that is the case is that the meta data triggering such criteria is automatically populated, this can be achieved through many approaches including Content Profiles Criteria workflows are configured and managed in WebCenter Content Administration Applets where you can configure one or more workflows. When you configured Criteria workflows the Content Presenter will support the editors with the approval process directly inline in the "Contribution mode" of the portal. In addition to approve/reject and details of the task, the content presenter natively support the user to view the current and future version of the change he/she is approving. See below for example: Architectural recommendation To support review&approval processes - minimize the amount of data files per page Each CMIS query can consume significant time depending on the complexity of the query - minimize the amount of CMIS queries per page Use Content Presenter Templates based on ADF - this way you minimize the design considerations and optimize the usage of caching Implement the page in as few Data files as possible - simplifies publishing process, increases performance and simplifies release process Named data file (node) or list of named nodes when integrating to pages increases performance vs. querying for data Named data file (node) or list of named nodes when integrating to pages enables business centric page creation and publishing and reduces the need for IT department interaction Summary Just because one architectural decision solves a business problem it doesn't mean its the right one, when designing portals all architecture has to be in harmony and not impacting each other. For instance the most technical complex solution is not always the best since it will most likely defeat the business accessibility, performance or both, therefore the best approach is to first design for simplicity that even a non-technical user can operate, after that consider the performance impact and final look at the technology challenges these brings and workaround them first with out-of-the-box features, after that design and develop functions to complement the short comings.

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• Coming to OpenWorld? A must attend session…

  - by Ruma Sanyal

  Normal 0 false false false EN-US X-NONE X-NONE NTT Docomo, Inc. is the predominant mobile phone operator in Japan. The name is officially an abbreviation of the phrase, "do communications over the mobile network", and is also from a compound word dokomo, meaning "everywhere" in Japanese.  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} One of the most important of NTT Docomo’s systems is ALADIN, which is a nationwide operating system shared with its eight regional subsidiaries. ALADIN has five primary functions: customer management, phone number management, information processing and storage, sales information management, and credit investigation. To enhance cost efficiency and help ensure stable operation of ALADIN, NTT Docomo has employed Oracle WebLogic Server as a new application platform. Further information on this can be found here. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Last year at OpenWorld, NTT Docomo was honored as an Innovation Award Winner for: · Implementing real time sales and contract management system enabling all services requested by customers for immediate activations before customer leaves the Docomo store · A robust disaster recovery strategy, room to grow the business, and ability to move custom Java development to a platform with built in standards - WebLogic · Better performance, better reliability, better stability, and smooth migration v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Normal 0 false false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Meet This Year's Most Impressive Innovators! This year we continue to honor customers for their most innovative and cutting-edge solutions using Oracle Fusion Middleware. Join us in celebrating award recipients’ great achievements and commitment to innovation.   Oracle Fusion Middleware: Meet This Year's Most Impressive Innovators Session ID: CON7029 Tuesday September 30, 2014 @ 5-5:45 pm (PST) Yerba Buena Center for the Arts  YBCA Theater (next to Moscone North) 700 Howard St., San Francisco, CA, 94103 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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• Using SQL Execution Plans to discover the Swedish alphabet

  - by Rob Farley

  SQL Server is quite remarkable in a bunch of ways. In this post, I’m using the way that the Query Optimizer handles LIKE to keep it SARGable, the Execution Plans that result, Collations, and PowerShell to come up with the Swedish alphabet. SARGability is the ability to seek for items in an index according to a particular set of criteria. If you don’t have SARGability in play, you need to scan the whole index (or table if you don’t have an index). For example, I can find myself in the phonebook easily, because it’s sorted by LastName and I can find Farley in there by moving to the Fs, and so on. I can’t find everyone in my suburb easily, because the phonebook isn’t sorted that way. I can’t even find people who have six letters in their last name, because also the book is sorted by LastName, it’s not sorted by LEN(LastName). This is all stuff I’ve looked at before, including in the talk I gave at SQLBits in October 2010. If I try to find everyone who’s names start with F, I can do that using a query a bit like: SELECT LastName FROM dbo.PhoneBook WHERE LEFT(LastName,1) = 'F'; Unfortunately, the Query Optimizer doesn’t realise that all the entries that satisfy LEFT(LastName,1) = 'F' will be together, and it has to scan the whole table to find them. But if I write: SELECT LastName FROM dbo.PhoneBook WHERE LastName LIKE 'F%'; then SQL is smart enough to understand this, and performs an Index Seek instead. To see why, I look further into the plan, in particular, the properties of the Index Seek operator. The ToolTip shows me what I’m after: You’ll see that it does a Seek to find any entries that are at least F, but not yet G. There’s an extra Predicate in there (a Residual Predicate if you like), which checks that each LastName is really LIKE F% – I suppose it doesn’t consider that the Seek Predicate is quite enough – but most of the benefit is seen by its working out the Seek Predicate, filtering to just the “at least F but not yet G” section of the data. This got me curious though, particularly about where the G comes from, and whether I could leverage it to create the Swedish alphabet. I know that in the Swedish language, there are three extra letters that appear at the end of the alphabet. One of them is ä that appears in the word Västerås. It turns out that Västerås is quite hard to find in an index when you’re looking it up in a Swedish map. I talked about this briefly in my five-minute talk on Collation from SQLPASS (the one which was slightly less than serious). So by looking at the plan, I can work out what the next letter is in the alphabet of the collation used by the column. In other words, if my alphabet were Swedish, I’d be able to tell what the next letter after F is – just in case it’s not G. It turns out it is… Yes, the Swedish letter after F is G. But I worked this out by using a copy of my PhoneBook table that used the Finnish_Swedish_CI_AI collation. I couldn’t find how the Query Optimizer calculates the G, and my friend Paul White (@SQL_Kiwi) tells me that it’s frustratingly internal to the QO. He’s particularly smart, even if he is from New Zealand. To investigate further, I decided to do some PowerShell, leveraging the Get-SqlPlan function that I blogged about recently (make sure you also have the SqlServerCmdletSnapin100 snap-in added). I started by indicating that I was going to use Finnish_Swedish_CI_AI as my collation of choice, and that I’d start whichever letter cam straight after the number 9. I figure that this is a cheat’s way of guessing the first letter of the alphabet (but it doesn’t actually work in Unicode – luckily I’m using varchar not nvarchar. Actually, there are a few aspects of this code that only work using ASCII, so apologies if you were wanting to apply it to Greek, Japanese, etc). I also initialised my $alphabet variable. $collation = 'Finnish_Swedish_CI_AI'; $firstletter = '9'; $alphabet = ''; Now I created the table for my test. A single field would do, and putting a Clustered Index on it would suffice for the Seeks. Invoke-Sqlcmd -server . -data tempdb -query "create table dbo.collation_test (col varchar(10) collate $collation primary key);" Now I get into the looping. $c = $firstletter; $stillgoing = $true; while ($stillgoing) { I construct the query I want, seeking for entries which start with whatever $c has reached, and get the plan for it: $query = "select col from dbo.collation_test where col like '$($c)%';"; [xml] $pl = get-sqlplan $query "." "tempdb"; At this point, my $pl variable is a scary piece of XML, representing the execution plan. A bit of hunting through it showed me that the EndRange element contained what I was after, and that if it contained NULL, then I was done. $stillgoing = ($pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange -ne $null); Now I could grab the value out of it (which came with apostrophes that needed stripping), and append that to my $alphabet variable.   if ($stillgoing)   {  $c=$pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange.RangeExpressions.ScalarOperator.ScalarString.Replace("'","");     $alphabet += $c;   } Finally, finishing the loop, dropping the table, and showing my alphabet! } Invoke-Sqlcmd -server . -data tempdb -query "drop table dbo.collation_test;"; $alphabet; When I run all this, I see that the Swedish alphabet is ABCDEFGHIJKLMNOPQRSTUVXYZÅÄÖ, which matches what I see at Wikipedia. Interesting to see that the letters on the end are still there, even with Case Insensitivity. Turns out they’re not just “letters with accents”, they’re letters in their own right. I’m sure you gave up reading long ago, and really aren’t that fazed about the idea of doing this using PowerShell. I chose PowerShell because I’d already come up with an easy way of grabbing the estimated plan for a query, and PowerShell does allow for easy navigation of XML. I find the most interesting aspect of this as the fact that the Query Optimizer uses the next letter of the alphabet to maintain the SARGability of LIKE. I’m hoping they do something similar for a whole bunch of operations. Oh, and the fact that you know how to find stuff in the IKEA catalogue. Footnote: If you are interested in whether this works in other languages, you might want to consider the following screenshot, which shows that in principle, it should work with Japanese. It might be a bit harder to run this in PowerShell though, as I’m not sure how it translates. In Hiragana, the Japanese alphabet starts ?, ?, ?, ?, ?, ...

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