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  • Samba with Active Directory - shares are readonly, NT_STATUS_MEDIA_WRITE_PROTECTED

    - by froh42
    I've set a samba server that seems to work, all shares are seemingly exported as readonly, however. The machine is called "lx". When I'm on lx I can run the following command: froh@lx:~$ smbclient //lx/export -UAdministrator Enter Administrator's password: Domain=[CUSTOMER] OS=[Unix] Server=[Samba 3.5.4] smb: \> mkdir wrzlbrmpf NT_STATUS_MEDIA_WRITE_PROTECTED making remote directory \wrzlbrmpf smb: \> ls . D 0 Fri Dec 3 19:04:20 2010 .. D 0 Sun Nov 28 01:32:37 2010 zork D 0 Fri Dec 3 18:53:33 2010 bar D 0 Sun Nov 28 23:52:43 2010 ork 1 Fri Dec 3 18:53:02 2010 foo 1 Sun Nov 28 23:52:41 2010 gaga D 0 Fri Dec 3 19:04:20 2010 How can I troubleshoot this? What I did: First I set up a fresh install of Ubuntu 10.10 x64. Second I got kerberos working with the following krb5.conf file: [libdefaults] ticket_lifetime = 24000 clock_skew = 300 default_realm = CUSTOMER.LOCAL [realms] CUSTOMER.LOCAL = { kdc = SB4.customer.local:88 admin_server = SB4.customer.local:464 default_domain = CUSTOMER.LOCAL } [domain_realm] .customer.local = CUSTOMER.LOCAL customer.local = CUSTOMER.LOCAL #[login] # krb4_convert = true # krb4_get_tickets = false I also added winbind to group, passwd and shadow in nsswitch.conf. Seemingly Kerberos works: root@lx:~# net ads testjoin Join is OK root@lx:~# wbinfo -a 'Administrator%MYSECRETPASSWORD' plaintext password authentication succeeded challenge/response password authentication succeeded wbinfo -u and wbinfo -g also spit out a list of users and a list of groups respectiveley. I noted that domain accounts did NOT include a domain and they are in german (as on the SBS 2003 that is the domain server). So I get a "Domänenbenutzer" in wbinfo -u's output not a "CUSTOMER+Domain User" or something similar. I'm not sure anymore what I did to the PAM configuration, but here is what I currently have: root@lx:/etc/pam.d# cat samba @include common-auth @include common-account @include common-session-noninteractive root@lx:/etc/pam.d# grep -ve '^#' common-auth auth [success=3 default=ignore] pam_krb5.so minimum_uid=1000 auth [success=2 default=ignore] pam_unix.so nullok_secure try_first_pass auth [success=1 default=ignore] pam_winbind.so krb5_auth krb5_ccache_type=FILE cached_login try_first_pass auth requisite pam_deny.so auth required pam_permit.so root@lx:/etc/pam.d# grep -ve '^#' common-account account [success=2 new_authtok_reqd=done default=ignore] pam_unix.so account [success=1 new_authtok_reqd=done default=ignore] pam_winbind.so account requisite pam_deny.so account required pam_permit.so account required pam_krb5.so minimum_uid=1000 root@lx:/etc/pam.d# grep -ve '^#' common-session-noninteractive session [default=1] pam_permit.so session requisite pam_deny.so session required pam_permit.so session optional pam_krb5.so minimum_uid=1000 session required pam_unix.so session optional pam_winbind.so At some point I joined the linux box into the AD domain. After (manually) creating a home directory on the linux box I can log in using the Adminstrator user with the password taken from AD. Now I run samba with the following setup: [global] netbios name = LX realm = CUSTOMER.LOCAL workgroup = CUSTOMER security = ADS encrypt passwords = yes password server = 192.168.20.244 #IP des Domain Controllers os level = 0 socket options = TCP_NODELAY SO_RCVBUF=16384 SO_SNDBUF=16384 idmap uid = 10000-20000 idmap gid = 10000-20000 winbind enum users = Yes winbind enum groups = Yes preferred master = no winbind separator = + dns proxy = no wins proxy = no # client NTLMv2 auth = Yes log level = 2 logfile = /var/log/samba/log.smbd.%U template homedir = /home/%U template shell = /bin/bash [export] path = /mnt/sdc1/export read only = No public = Yes Currently I don't care whether export is exported to everyone or just one user, I want to see somebody WRITING to that directory before I start fiddling with the authentication settings. (Who may access it). As mentioned, accessing the share from smbclient results in this NT_STATUS_MEDIA_WRITE_PROTECTED . Accessing it from windows shows ACLs that look correct (The user may write) - but it does not work, I can only read files not write. The directory to be exported looks like this: root@lx:/etc/pam.d# ls -ld /mnt/ drwxr-xr-x 5 root root 4096 2010-11-28 01:29 /mnt/ root@lx:/etc/pam.d# ls -ld /mnt/sdc1/ drwxr-xr-x 4 froh froh 4096 2010-11-28 01:32 /mnt/sdc1/ root@lx:/etc/pam.d# ls -ld /mnt/sdc1/export/ drwxrwxrwx+ 5 administrator domänen-admins 4096 2010-12-03 19:04 /mnt/sdc1/export/ root@lx:/etc/pam.d# getfacl /mnt/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/ # owner: root # group: root user::rwx group::r-x other::r-x root@lx:/etc/pam.d# getfacl /mnt/sdc1/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/sdc1/ # owner: froh # group: froh user::rwx group::r-x other::r-x root@lx:/etc/pam.d# getfacl /mnt/sdc1/export/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/sdc1/export/ # owner: administrator # group: domänen-admins user::rwx group::rwx group:domänen-admins:rwx mask::rwx other::rwx default:user::rwx default:group::rwx default:group:domänen-admins:rwx default:mask::rwx default:other::rwx My, oh my what am I overlooking? What am I to blind to see?

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  • Samba with Active Directory - shares are readonly, NT_STATUS_MEDIA_WRITE_PROTECTED

    - by froh42
    I've set a samba server that seems to work, all shares are seemingly exported as readonly, however. The machine is called "lx". When I'm on lx I can run the following command: froh@lx:~$ smbclient //lx/export -UAdministrator Enter Administrator's password: Domain=[CUSTOMER] OS=[Unix] Server=[Samba 3.5.4] smb: \> mkdir wrzlbrmpf NT_STATUS_MEDIA_WRITE_PROTECTED making remote directory \wrzlbrmpf smb: \> ls . D 0 Fri Dec 3 19:04:20 2010 .. D 0 Sun Nov 28 01:32:37 2010 zork D 0 Fri Dec 3 18:53:33 2010 bar D 0 Sun Nov 28 23:52:43 2010 ork 1 Fri Dec 3 18:53:02 2010 foo 1 Sun Nov 28 23:52:41 2010 gaga D 0 Fri Dec 3 19:04:20 2010 How can I troubleshoot this? What I did: First I set up a fresh install of Ubuntu 10.10 x64. Second I got kerberos working with the following krb5.conf file: [libdefaults] ticket_lifetime = 24000 clock_skew = 300 default_realm = CUSTOMER.LOCAL [realms] CUSTOMER.LOCAL = { kdc = SB4.customer.local:88 admin_server = SB4.customer.local:464 default_domain = CUSTOMER.LOCAL } [domain_realm] .customer.local = CUSTOMER.LOCAL customer.local = CUSTOMER.LOCAL #[login] # krb4_convert = true # krb4_get_tickets = false I also added winbind to group, passwd and shadow in nsswitch.conf. Seemingly Kerberos works: root@lx:~# net ads testjoin Join is OK root@lx:~# wbinfo -a 'Administrator%MYSECRETPASSWORD' plaintext password authentication succeeded challenge/response password authentication succeeded wbinfo -u and wbinfo -g also spit out a list of users and a list of groups respectiveley. I noted that domain accounts did NOT include a domain and they are in german (as on the SBS 2003 that is the domain server). So I get a "Domänenbenutzer" in wbinfo -u's output not a "CUSTOMER+Domain User" or something similar. I'm not sure anymore what I did to the PAM configuration, but here is what I currently have: root@lx:/etc/pam.d# cat samba @include common-auth @include common-account @include common-session-noninteractive root@lx:/etc/pam.d# grep -ve '^#' common-auth auth [success=3 default=ignore] pam_krb5.so minimum_uid=1000 auth [success=2 default=ignore] pam_unix.so nullok_secure try_first_pass auth [success=1 default=ignore] pam_winbind.so krb5_auth krb5_ccache_type=FILE cached_login try_first_pass auth requisite pam_deny.so auth required pam_permit.so root@lx:/etc/pam.d# grep -ve '^#' common-account account [success=2 new_authtok_reqd=done default=ignore] pam_unix.so account [success=1 new_authtok_reqd=done default=ignore] pam_winbind.so account requisite pam_deny.so account required pam_permit.so account required pam_krb5.so minimum_uid=1000 root@lx:/etc/pam.d# grep -ve '^#' common-session-noninteractive session [default=1] pam_permit.so session requisite pam_deny.so session required pam_permit.so session optional pam_krb5.so minimum_uid=1000 session required pam_unix.so session optional pam_winbind.so At some point I joined the linux box into the AD domain. After (manually) creating a home directory on the linux box I can log in using the Adminstrator user with the password taken from AD. Now I run samba with the following setup: [global] netbios name = LX realm = CUSTOMER.LOCAL workgroup = CUSTOMER security = ADS encrypt passwords = yes password server = 192.168.20.244 #IP des Domain Controllers os level = 0 socket options = TCP_NODELAY SO_RCVBUF=16384 SO_SNDBUF=16384 idmap uid = 10000-20000 idmap gid = 10000-20000 winbind enum users = Yes winbind enum groups = Yes preferred master = no winbind separator = + dns proxy = no wins proxy = no # client NTLMv2 auth = Yes log level = 2 logfile = /var/log/samba/log.smbd.%U template homedir = /home/%U template shell = /bin/bash [export] path = /mnt/sdc1/export read only = No public = Yes Currently I don't care whether export is exported to everyone or just one user, I want to see somebody WRITING to that directory before I start fiddling with the authentication settings. (Who may access it). As mentioned, accessing the share from smbclient results in this NT_STATUS_MEDIA_WRITE_PROTECTED . Accessing it from windows shows ACLs that look correct (The user may write) - but it does not work, I can only read files not write. The directory to be exported looks like this: root@lx:/etc/pam.d# ls -ld /mnt/ drwxr-xr-x 5 root root 4096 2010-11-28 01:29 /mnt/ root@lx:/etc/pam.d# ls -ld /mnt/sdc1/ drwxr-xr-x 4 froh froh 4096 2010-11-28 01:32 /mnt/sdc1/ root@lx:/etc/pam.d# ls -ld /mnt/sdc1/export/ drwxrwxrwx+ 5 administrator domänen-admins 4096 2010-12-03 19:04 /mnt/sdc1/export/ root@lx:/etc/pam.d# getfacl /mnt/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/ # owner: root # group: root user::rwx group::r-x other::r-x root@lx:/etc/pam.d# getfacl /mnt/sdc1/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/sdc1/ # owner: froh # group: froh user::rwx group::r-x other::r-x root@lx:/etc/pam.d# getfacl /mnt/sdc1/export/ getfacl: Entferne führende '/' von absoluten Pfadnamen # file: mnt/sdc1/export/ # owner: administrator # group: domänen-admins user::rwx group::rwx group:domänen-admins:rwx mask::rwx other::rwx default:user::rwx default:group::rwx default:group:domänen-admins:rwx default:mask::rwx default:other::rwx My, oh my what am I overlooking? What am I to blind to see?

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  • LLBLGen Pro feature highlights: automatic element name construction

    - by FransBouma
    (This post is part of a series of posts about features of the LLBLGen Pro system) One of the things one might take for granted but which has a huge impact on the time spent in an entity modeling environment is the way the system creates names for elements out of the information provided, in short: automatic element name construction. Element names are created in both directions of modeling: database first and model first and the more names the system can create for you without you having to rename them, the better. LLBLGen Pro has a rich, fine grained system for creating element names out of the meta-data available, which I'll describe more in detail below. First the model element related element naming features are highlighted, in the section Automatic model element naming features and after that I'll go more into detail about the relational model element naming features LLBLGen Pro has to offer in the section Automatic relational model element naming features. Automatic model element naming features When working database first, the element names in the model, e.g. entity names, entity field names and so on, are in general determined from the relational model element (e.g. table, table field) they're mapped on, as the model elements are reverse engineered from these relational model elements. It doesn't take rocket science to automatically name an entity Customer if the entity was created after reverse engineering a table named Customer. It gets a little trickier when the entity which was created by reverse engineering a table called TBL_ORDER_LINES has to be named 'OrderLine' automatically. Automatic model element naming also takes into effect with model first development, where some settings are used to provide you with a default name, e.g. in the case of navigator name creation when you create a new relationship. The features below are available to you in the Project Settings. Open Project Settings on a loaded project and navigate to Conventions -> Element Name Construction. Strippers! The above example 'TBL_ORDER_LINES' shows that some parts of the table name might not be needed for name creation, in this case the 'TBL_' prefix. Some 'brilliant' DBAs even add suffixes to table names, fragments you might not want to appear in the entity names. LLBLGen Pro offers you to define both prefix and suffix fragments to strip off of table, view, stored procedure, parameter, table field and view field names. In the example above, the fragment 'TBL_' is a good candidate for such a strip pattern. You can specify more than one pattern for e.g. the table prefix strip pattern, so even a really messy schema can still be used to produce clean names. Underscores Be Gone Another thing you might get rid of are underscores. After all, most naming schemes for entities and their classes use PasCal casing rules and don't allow for underscores to appear. LLBLGen Pro can automatically strip out underscores for you. It's an optional feature, so if you like the underscores, you're not forced to see them go: LLBLGen Pro will leave them alone when ordered to to so. PasCal everywhere... or not, your call LLBLGen Pro can automatically PasCal case names on word breaks. It determines word breaks in a couple of ways: a space marks a word break, an underscore marks a word break and a case difference marks a word break. It will remove spaces in all cases, and based on the underscore removal setting, keep or remove the underscores, and upper-case the first character of a word break fragment, and lower case the rest. Say, we keep the defaults, which is remove underscores and PasCal case always and strip the TBL_ fragment, we get with our example TBL_ORDER_LINES, after stripping TBL_ from the table name two word fragments: ORDER and LINES. The underscores are removed, the first character of each fragment is upper-cased, the rest lower-cased, so this results in OrderLines. Almost there! Pluralization and Singularization In general entity names are singular, like Customer or OrderLine so LLBLGen Pro offers a way to singularize the names. This will convert OrderLines, the result we got after the PasCal casing functionality, into OrderLine, exactly what we're after. Show me the patterns! There are other situations in which you want more flexibility. Say, you have an entity Customer and an entity Order and there's a foreign key constraint defined from the target of Order and the target of Customer. This foreign key constraint results in a 1:n relationship between the entities Customer and Order. A relationship has navigators mapped onto the relationship in both entities the relationship is between. For this particular relationship we'd like to have Customer as navigator in Order and Orders as navigator in Customer, so the relationship becomes Customer.Orders 1:n Order.Customer. To control the naming of these navigators for the various relationship types, LLBLGen Pro defines a set of patterns which allow you, using macros, to define how the auto-created navigator names will look like. For example, if you rather have Customer.OrderCollection, you can do so, by changing the pattern from {$EndEntityName$P} to {$EndEntityName}Collection. The $P directive makes sure the name is pluralized, which is not what you want if you're going for <EntityName>Collection, hence it's removed. When working model first, it's a given you'll create foreign key fields along the way when you define relationships. For example, you've defined two entities: Customer and Order, and they have their fields setup properly. Now you want to define a relationship between them. This will automatically create a foreign key field in the Order entity, which reflects the value of the PK field in Customer. (No worries if you hate the foreign key fields in your classes, on NHibernate and EF these can be hidden in the generated code if you want to). A specific pattern is available for you to direct LLBLGen Pro how to name this foreign key field. For example, if all your entities have Id as PK field, you might want to have a different name than Id as foreign key field. In our Customer - Order example, you might want to have CustomerId instead as foreign key name in Order. The pattern for foreign key fields gives you that freedom. Abbreviations... make sense of OrdNr and friends I already described word breaks in the PasCal casing paragraph, how they're used for the PasCal casing in the constructed name. Word breaks are used for another neat feature LLBLGen Pro has to offer: abbreviation support. Burt, your friendly DBA in the dungeons below the office has a hate-hate relationship with his keyboard: he can't stand it: typing is something he avoids like the plague. This has resulted in tables and fields which have names which are very short, but also very unreadable. Example: our TBL_ORDER_LINES example has a lovely field called ORD_NR. What you would like to see in your fancy new OrderLine entity mapped onto this table is a field called OrderNumber, not a field called OrdNr. What you also like is to not have to rename that field manually. There are better things to do with your time, after all. LLBLGen Pro has you covered. All it takes is to define some abbreviation - full word pairs and during reverse engineering model elements from tables/views, LLBLGen Pro will take care of the rest. For the ORD_NR field, you need two values: ORD as abbreviation and Order as full word, and NR as abbreviation and Number as full word. LLBLGen Pro will now convert every word fragment found with the word breaks which matches an abbreviation to the given full word. They're case sensitive and can be found in the Project Settings: Navigate to Conventions -> Element Name Construction -> Abbreviations. Automatic relational model element naming features Not everyone works database first: it may very well be the case you start from scratch, or have to add additional tables to an existing database. For these situations, it's key you have the flexibility that you can control the created table names and table fields without any work: let the designer create these names based on the entity model you defined and a set of rules. LLBLGen Pro offers several features in this area, which are described in more detail below. These features are found in Project Settings: navigate to Conventions -> Model First Development. Underscores, welcome back! Not every database is case insensitive, and not every organization requires PasCal cased table/field names, some demand all lower or all uppercase names with underscores at word breaks. Say you create an entity model with an entity called OrderLine. You work with Oracle and your organization requires underscores at word breaks: a table created from OrderLine should be called ORDER_LINE. LLBLGen Pro allows you to do that: with a simple checkbox you can order LLBLGen Pro to insert an underscore at each word break for the type of database you're working with: case sensitive or case insensitive. Checking the checkbox Insert underscore at word break case insensitive dbs will let LLBLGen Pro create a table from the entity called Order_Line. Half-way there, as there are still lower case characters there and you need all caps. No worries, see below Casing directives so everyone can sleep well at night For case sensitive databases and case insensitive databases there is one setting for each of them which controls the casing of the name created from a model element (e.g. a table created from an entity definition using the auto-mapping feature). The settings can have the following values: AsProjectElement, AllUpperCase or AllLowerCase. AsProjectElement is the default, and it keeps the casing as-is. In our example, we need to get all upper case characters, so we select AllUpperCase for the setting for case sensitive databases. This will produce the name ORDER_LINE. Sequence naming after a pattern Some databases support sequences, and using model-first development it's key to have sequences, when needed, to be created automatically and if possible using a name which shows where they're used. Say you have an entity Order and you want to have the PK values be created by the database using a sequence. The database you're using supports sequences (e.g. Oracle) and as you want all numeric PK fields to be sequenced, you have enabled this by the setting Auto assign sequences to integer pks. When you're using LLBLGen Pro's auto-map feature, to create new tables and constraints from the model, it will create a new table, ORDER, based on your settings I previously discussed above, with a PK field ID and it also creates a sequence, SEQ_ORDER, which is auto-assigns to the ID field mapping. The name of the sequence is created by using a pattern, defined in the Model First Development setting Sequence pattern, which uses plain text and macros like with the other patterns previously discussed. Grouping and schemas When you start from scratch, and you're working model first, the tables created by LLBLGen Pro will be in a catalog and / or schema created by LLBLGen Pro as well. If you use LLBLGen Pro's grouping feature, which allows you to group entities and other model elements into groups in the project (described in a future blog post), you might want to have that group name reflected in the schema name the targets of the model elements are in. Say you have a model with a group CRM and a group HRM, both with entities unique for these groups, e.g. Employee in HRM, Customer in CRM. When auto-mapping this model to create tables, you might want to have the table created for Employee in the HRM schema but the table created for Customer in the CRM schema. LLBLGen Pro will do just that when you check the setting Set schema name after group name to true (default). This gives you total control over where what is placed in the database from your model. But I want plural table names... and TBL_ prefixes! For now we follow best practices which suggest singular table names and no prefixes/suffixes for names. Of course that won't keep everyone happy, so we're looking into making it possible to have that in a future version. Conclusion LLBLGen Pro offers a variety of options to let the modeling system do as much work for you as possible. Hopefully you enjoyed this little highlight post and that it has given you new insights in the smaller features available to you in LLBLGen Pro, ones you might not have thought off in the first place. Enjoy!

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  • SSAS deployment error: Internal error: Invalid enumeration value. Please call customer support! is not a valid value for this element.

    - by Kevin Shyr
    The first search on this error yielded some blog posts that says to check SQL server version.  It suggested that I couldn't deploy a SSAS project originally set for SSAS 2008 to a SSAS 2008 R2, which didn't make sense to me.  Combined with the fact that the error message was telling me to call customer support.  Why do I need to call customer support unless something catastrophic happened?Turns out that one of the file on the SQL server is corrupt.  I could simply delete the database on the SSAS server and re-run deployment.  Problem solved.SSAS errors in visual studio: Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in; mso-para-margin-bottom:.0001pt; 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-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Error      10           Internal error: Invalid enumeration value. Please call customer support! is not a valid value for this element.                                0              0              Error      11           An error occurred while parsing the 'StorageMode' element at line 1, column 10523 ('http://schemas.microsoft.com/analysisservices/2003/engine' namespace) under Load/ObjectDefinition/Dimension/StorageMode.                            0              0              Error      12           Errors in the metadata manager. An error occurred when instantiating a metadata object from the file, '\\?\E:\Program Files\Microsoft SQL Server\MSAS10_50.MSSQLSERVER\OLAP\Data\DWH Sales Facts.0.db\Competitor.48.dim.xml'.                        0              0

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  • Oracle Data Mining a Star Schema: Telco Churn Case Study

    - by charlie.berger
    There is a complete and detailed Telco Churn case study "How to" Blog Series just posted by Ari Mozes, ODM Dev. Manager.  In it, Ari provides detailed guidance in how to leverage various strengths of Oracle Data Mining including the ability to: mine Star Schemas and join tables and views together to obtain a complete 360 degree view of a customer combine transactional data e.g. call record detail (CDR) data, etc. define complex data transformation, model build and model deploy analytical methodologies inside the Database  His blog is posted in a multi-part series.  Below are some opening excerpts for the first 3 blog entries.  This is an excellent resource for any novice to skilled data miner who wants to gain competitive advantage by mining their data inside the Oracle Database.  Many thanks Ari! Mining a Star Schema: Telco Churn Case Study (1 of 3) One of the strengths of Oracle Data Mining is the ability to mine star schemas with minimal effort.  Star schemas are commonly used in relational databases, and they often contain rich data with interesting patterns.  While dimension tables may contain interesting demographics, fact tables will often contain user behavior, such as phone usage or purchase patterns.  Both of these aspects - demographics and usage patterns - can provide insight into behavior.Churn is a critical problem in the telecommunications industry, and companies go to great lengths to reduce the churn of their customer base.  One case study1 describes a telecommunications scenario involving understanding, and identification of, churn, where the underlying data is present in a star schema.  That case study is a good example for demonstrating just how natural it is for Oracle Data Mining to analyze a star schema, so it will be used as the basis for this series of posts...... Mining a Star Schema: Telco Churn Case Study (2 of 3) This post will follow the transformation steps as described in the case study, but will use Oracle SQL as the means for preparing data.  Please see the previous post for background material, including links to the case study and to scripts that can be used to replicate the stages in these posts.1) Handling missing values for call data recordsThe CDR_T table records the number of phone minutes used by a customer per month and per call type (tariff).  For example, the table may contain one record corresponding to the number of peak (call type) minutes in January for a specific customer, and another record associated with international calls in March for the same customer.  This table is likely to be fairly dense (most type-month combinations for a given customer will be present) due to the coarse level of aggregation, but there may be some missing values.  Missing entries may occur for a number of reasons: the customer made no calls of a particular type in a particular month, the customer switched providers during the timeframe, or perhaps there is a data entry problem.  In the first situation, the correct interpretation of a missing entry would be to assume that the number of minutes for the type-month combination is zero.  In the other situations, it is not appropriate to assume zero, but rather derive some representative value to replace the missing entries.  The referenced case study takes the latter approach.  The data is segmented by customer and call type, and within a given customer-call type combination, an average number of minutes is computed and used as a replacement value.In SQL, we need to generate additional rows for the missing entries and populate those rows with appropriate values.  To generate the missing rows, Oracle's partition outer join feature is a perfect fit.  select cust_id, cdre.tariff, cdre.month, minsfrom cdr_t cdr partition by (cust_id) right outer join     (select distinct tariff, month from cdr_t) cdre     on (cdr.month = cdre.month and cdr.tariff = cdre.tariff);   ....... Mining a Star Schema: Telco Churn Case Study (3 of 3) Now that the "difficult" work is complete - preparing the data - we can move to building a predictive model to help identify and understand churn.The case study suggests that separate models be built for different customer segments (high, medium, low, and very low value customer groups).  To reduce the data to a single segment, a filter can be applied: create or replace view churn_data_high asselect * from churn_prep where value_band = 'HIGH'; It is simple to take a quick look at the predictive aspects of the data on a univariate basis.  While this does not capture the more complex multi-variate effects as would occur with the full-blown data mining algorithms, it can give a quick feel as to the predictive aspects of the data as well as validate the data preparation steps.  Oracle Data Mining includes a predictive analytics package which enables quick analysis. begin  dbms_predictive_analytics.explain(   'churn_data_high','churn_m6','expl_churn_tab'); end; /select * from expl_churn_tab where rank <= 5 order by rank; ATTRIBUTE_NAME       ATTRIBUTE_SUBNAME EXPLANATORY_VALUE RANK-------------------- ----------------- ----------------- ----------LOS_BAND                                      .069167052          1MINS_PER_TARIFF_MON  PEAK-5                   .034881648          2REV_PER_MON          REV-5                    .034527798          3DROPPED_CALLS                                 .028110322          4MINS_PER_TARIFF_MON  PEAK-4                   .024698149          5From the above results, it is clear that some predictors do contain information to help identify churn (explanatory value > 0).  The strongest uni-variate predictor of churn appears to be the customer's (binned) length of service.  The second strongest churn indicator appears to be the number of peak minutes used in the most recent month.  The subname column contains the interior piece of the DM_NESTED_NUMERICALS column described in the previous post.  By using the object relational approach, many related predictors are included within a single top-level column. .....   NOTE:  These are just EXCERPTS.  Click here to start reading the Oracle Data Mining a Star Schema: Telco Churn Case Study from the beginning.    

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  • Customer Insight. Trend, Modelli e Tecnologie di Successo nel CRM di ultima generazione

    - by antonella.buonagurio(at)oracle.com
    Lo scorso 27 gennaio a Roma si è tenuta la 3° tappa del CRM On Demand Roadshow. L'iniziativa è stata un un momento di incontro e confronto tra Direttori Marketing, esperti di CRM e Direttori Sales, sui nuovi trend del marketing relazionale.   Grazie altri interventi di ItalTBS, Bricofer, Renault Italia, Avis,  IRCCS, San Raffale e con la moderazione del Prof. Maurizio Mesenzani  si sono condivise idee, esperienze, riflessioni sugli strumenti che ad oggi si sono dimostrati essere i  più efficaci per individuare i bisogni del cliente, trasformare i clienti potenziali in clienti soddisfatti, creare engagement. Continua a leggere per vedere le presentazioni

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  • Know Your Service Request Status

    - by Get Proactive Customer Adoption Team
    Untitled Document To monitor a Service Request or not to monitor a Service Request... That should never be the question Monitoring the Service Requests you create is an essential part of the process to resolve your issue when you work with a Support Engineer. If you monitor your Service Request, you know at all times where it is in the process, or to be more specific, you know at all times what action the Support Engineer has taken on your request and what the next step is. When you think about it, it is rather simple... Oracle Support is working the issue, Oracle Development is working the issue, or you are. When you check on the status, you may find that the Support Engineer has a question for you or the engineer is waiting for more information to resolve the issue. If you monitor the Service Request, and respond quickly, the process keeps moving, and you’ll get your answer more quickly. Monitoring a Service Request is easy. All you need to do is check the status codes that the Support Engineer or the system assigns to your Service Request. These status codes are not static. You will see that during the life of your Service request, it will go through a variety of status codes. The best advice I can offer you when you monitor your Service Request is to watch the codes. If the status is not changing, or if you are not getting responses back within the agreed timeframes, you should review the action plan the Support Engineer has outlined or talk about a new action plan. Here are the most common status codes: Work in Progress indicates that your Support Engineer is researching and working the issue. Development Working means that you have a code related issue and Oracle Support has submitted a bug to Development. Please pay a particular attention to the following statuses; they indicate that the Support Engineer is waiting for a response from you: Customer Working usually means that your Support Engineer needs you to collect additional information, needs you to try something or to apply a patch, or has more questions for you. Solution Offered indicates that the Support Engineer has identified the problem and has provided you with a solution. Auto-Close or Close Initiated are statuses you don’t want to see. Monitoring your Service Request helps prevent your issues from reaching these statuses. They usually indicate that the Support Engineer did not receive the requested information or action from you. This is important. If you fail to respond, the Support Engineer will attempt to contact you three times over a two-week period. If these attempts are unsuccessful, he or she will initiate the Auto-Close process. At the end of this additional two-week period, if you have not updated the Service Request, your Service Request is considered abandoned and the Support Engineer will assign a Customer Abandoned status. A Support Engineer doesn’t like to see this status, since he or she has been working to solve your issue, but we know our customers dislike it even more, since it means their issue is not moving forward. You can avoid delays in resolving your issue by monitoring your Service Request and acting quickly when you see the status change. Respond to the request from the engineer to answer questions, collect information, or to try the offered solution. Then the Support Engineer can continue working the issue and the Service Request keeps moving forward towards resolution. Keep in mind that if you take an extended period of time to respond to a request or to provide the information requested, the Support Engineer cannot take the next step. You may inadvertently send an implicit message about the problem’s urgency that may not match the Service Request priority, and your need for an answer. Help us help you. We want to get you the answer as quickly as possible so you can stay focused on your company’s objectives. Now, back to our initial question. To monitor Service Requests or not to monitor Service Requests? I think the answer is clear: yes, monitor your Service Request to resolve the issue as quickly as possible.

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  • Customer escalated to a claim without sending the item back? [closed]

    - by kavoir.com
    She claims that she has sent the item back but for over 1 month I haven't received it. I don't know where I can find the tracking number so I don't know if she really sent it or not. Now she has escalated the dispute to claim and PayPal is asking me for information. The reason is "Not as described". So how do I respond to this? I mean, in the dispute, we agreed that I'll issue a full refund as soon as I receive the package she return to us but we never received this package that she claimed to have sent back. Now she's escalating this to a claim and PayPal is asking me for documents. How can I provide any documents that would prove she hasn't sent the package? Thanks!

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  • ecommerce platform or from scratch? customer specific catalogs and purchase orders

    - by rafi
    I have a possible freelance job in front of me for a distributor who wants product ordering set up but the orders are all P.O.s basically - no actual credit card or paypal transaction. The customer is simply billed and the order archived. Customers will need to login to this site and each customer will have their own custom catalog of a few dozen products which have been setup via a control panel this distributor uses. So there will be a master catalog of over 1,000 products (perhaps browsable but not to be ordered from on the site) but each customer will only be able to order from the products specified for their accounts. I know I can build this from scratch but I figured it's worth looking into what ecommerce platforms would get me a nice head start. Obviously shopping cart, order history, catalog management are concepts that I can reuse but are any of the ecommerce systems out there also capable of handling custom catalogs (maybe as multi-stores?) or transactions billed to accounts without credit card? The more I could reuse the better. I've messed with OSCommerce (way back) and a little Zen Cart more recently. I've also worked on a number of totally custom e-commerce sites. But my knowledge of the open source e-commerce tools is pretty limited and I'm trying to keep the effort as simple as I possibly can on this. I'm pretty flexible on the language of the platform by the way. Thanks in advance.

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  • Does AWS resolve same-datacenter hostnames to 10.* addresses for different customer accounts?

    - by Scott Ritchie
    If I bring up two Amazon EC2 instances and run nslookup on one for the other's hostname, amazon will return a 10.* address. This is routable within amazon, and works just fine. But does this work between different accounts? If I use one of my nodes to nslookup a hostname belonging to another customer (but still in the same datacenter) will it resolve as a 10.* address or will it give the standard public IP?

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  • ASP.NET MVC 2 RC2 Routing - How to clear low-level values when using ActionLink to refer to a higher

    - by Gary McGill
    [NOTE: I'm using ASP.NET MVC2 RC2.] I have URLs like this: /customer/123/order/456/item/index /customer/123/order/456/item/789/edit My routing table lists the most-specific routes first, so I've got: // customer/123/order/456/item/789/edit routes.MapRoute( "item", // Route name "customer/{customerId}/order/{orderId}/item/{itemId}/{action}", // URL with parameters new { controller = "Items", action = "Details" }, // Parameter defaults new { customerId = @"\d+", orderId = @"\d+", itemId = @"\d+" } // Constraints ); // customer/123/order/456/item/index routes.MapRoute( "items", // Route name "customer/{customerId}/order/{orderId}/item/{action}", // URL with parameters new { controller = "Items", action = "Index" }, // Parameter defaults new { customerId = @"\d+", orderId = @"\d+" } // Constraints ); When I'm in the "Edit" page, I want a link back up to the "Index" page. So, I use: ActionLink("Back to Index", "index") However, because there's an ambient order ID, this results in the URL: /Customer/123/Order/456/Item/789/Index ...whereas I want it to "forget" the order ID and just use: /Customer/123/Order/456/Item/Index I've tried overriding the order ID like so: ActionLink("Back to Index", "index", new { orderId=string.empty }) ...but that doesn't work. How can I persuade ActionLink to "forget" the order ID?

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  • Nhibernate one-to-many with table per subclass

    - by Wayne
    I am customizing N2CMS's database structure, and met with an issue. The two classes are listed below. public class Customer : ContentItem { public IList<License> Licenses { get; set; } } public class License : ContentItem { public Customer Customer { get; set; } } The nhibernate mapping are as follows. <class name="N2.ContentItem,N2" table="n2item"> <cache usage="read-write" /> <id name="ID" column="ID" type="Int32" unsaved-value="0" access="property"> <generator class="native" /> </id> <discriminator column="Type" type="String" /> </class> <subclass name="My.Customer,My" extends="N2.ContentItem,N2" discriminator-value="Customer"> <join table="Customer"> <key column="ItemID" /> <bag name="Licenses" generic="true" inverse="true"> <key column="CustomerID" /> <one-to-many class="My.License,My"/> </bag> </join> </subclass> <subclass name="My.License,My" extends="N2.ContentItem,N2" discriminator-value="License"> <join table="License" fetch="select"> <key column="ItemID" /> <many-to-one name="Customer" column="CustomerID" class="My.Customer,My" not-null="false" /> </join> </subclass> Then, when get an instance of Customer, the customer.Licenses is always empty, but actually there are licenses in the database for the customer. When I check the nhibernate log file, I find that the SQL query is like: SELECT licenses0_.CustomerID as CustomerID1_, licenses0_.ID as ID1_, licenses0_.ID as ID2_0_, licenses0_1_.CustomerID as CustomerID7_0_, FROM n2item licenses0_ inner join License licenses0_1_ on licenses0_.ID = licenses0_1_.ItemID WHERE licenses0_.CustomerID = 12 /* @p0 */ It seems that nhibernate believes that the CustomerID is in the 'n2item' table. I don't know why, but to make it work, I think the SQL should be something like this. SELECT licenses0_.ID as ID1_, licenses0_.ID as ID2_0_, licenses0_1_.CustomerID as CustomerID7_0_, FROM n2item licenses0_ inner join License licenses0_1_ on licenses0_.ID = licenses0_1_.ItemID WHERE licenses0_1_.CustomerID = 12 /* @p0 */ Could any one point out what's wrong with my mappings? And how can I get the correct licenses of one customer? Thanks in advance.

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  • SQL query optimization

    - by nvtthang
    I have a problem with my SQL query that take time to get all records from database. Any body help me. Below is a sample of database: order(order_id, order_nm) customer(customer_id, customer_nm) orderDetail(orderDetail_id, order_id, orderDate, customer_id, Comment) I want to get latest customer and order detail information. Here is may solution: I've created a function that GetLatestOrderByCustomer(CusID) to get lastest Customer information. CREATE FUNCTION [dbo].[GetLatestOrderByCustomer] ( @cus_id int ) RETURNS varchar(255) AS BEGIN DECLARE @ResultVar varchar(255) SELECT @ResultVar = tmp.comment FROM ( SELECT TOP 1 orderDate, comment FROM orderDetail WHERE orderDetail.customer_id = @cust_id ) tmp -- Return the result of the function RETURN @ResultVar END Below is my SQL query SELECT customer.customer_id , customer.customer_nm , dbo.GetLatestOrderByCustomer(customer.customer_id) FROM Customer LEFT JOIN orderDetail ON orderDetail.customer_id = customer.customer_id It's take time to run the function. Could anybody suggest me any solutions to make it better? Thanks in advance.

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  • Magento - Clean custom Account/Registration Fields

    - by Bizboss
    Hello, I followed this tutorial to add fields in the registration form of a customer under Magento, I succeed to run the example, but I know that It is not clean, for upates later... What' the best way to rewrite all the files used in the tutorial, in a clean way : app/design/frontend/default/yourtheme/template/customer/form/register.phtml app/design/frontend/default/yourtheme/template/customer/form/edit.phtml app/code/core/Mage/Customer/Model/Entity/Setup.php app/code/core/Mage/Customer/etc/config.xml app/code/core/Mage/Customer/controllers/AccountController.php Thanks a lot

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  • In my cakephp project the save function is not working?

    - by Faheem
    My controller action is: function add() { if (!empty($this-data)) { $this-Customer-create(); if ($this-Customer-save($this-data)) { $this-Session-setFlash('A new Customer has been added'); $this-redirect(array('action'='index')); } else { $this-Session-setFlash('The customer cannot be added this time. Try again later.'); $this-redirect(array('action'='index')); } } } My model is: class Customer extends AppModel { var $name = 'Customer'; var $validate = array( 'name' = array( 'length'= array( 'rule' = array('between', 4,50), 'message' = 'Name must be minimum 4 and maximum 50 characters long.' ), 'checkUnique'= array( 'rule' = 'isUnique', 'message' = 'This Name is already registered' ) )); and this is my view: create('Customer',array('action'='add'));? input('Customer.name'); echo $form-input('Customer.balance',array('type'='hidden','default'=0)); ? end('Submit');? every time I submit the form it splashes: The customer cannot be added this time. Try again later.

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  • Multi threading in WCF RIA Services

    - by synergetic
    I use WCF RIA Services to update customer database. In domain service: public void UpdateCustomer(Customer customer) { this.ObjectContext.Customers.AttachAsModified(customer); syncCustomer(customer); } After update, a database trigger launches and depending on the columns updated it may insert a new record in CustomerChange table. syncCustomer(customer) method is executed to check for a new record in the CustomerChange table and if found it will create a text file which contains customer information and forwards that file to external system for import. Now this synchronization may take a time so I wanted to execute it in different thread. So: private void syncCustomer(Customer customer) { this.ObjectContext.SaveChanges(); new Thread(() => syncCustomerInfo(customer.CustomerID)) { IsBackground = true }.Start(); } private void syncCustomerInfo(int customerID) { //Thread.Sleep(2000); //does real job here ... ... } The problem is in most cases syncCustomerInfo method cannot find any new CustomerChange record even if it was definitely there. If I force thread sleep then it finds a new record. I also looked Entity Framework events but the only event provided by object context is SavingChanges which occur before changes are saved. Please suggest me what else to try.

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  • Remove duplicates from a list

    - by Mercer
    Hello i want to remove duplicates from a list i do this but not working List<Customer> listCustomer = new ArrayList<Customer>(); for (Customer customer: tmpListCustomer) { if (!listCustomer.contains(customer)) { listCustomer.add(customer); } }

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  • Basic PHP OOPS Query

    - by appu
    Ok. I am starting out OOPS in PHP. Created a couple of classes: customer(parent) and sales(child) class that inherits from parent class. Created another testcustomer.php in which a new sales object is created however the salesprint() function defined in the sales class does not echo out customer's name though it is set to be "Jane" in the class.customer.php(parent). My thinking is that when sales class extends customer class PHP automatically includes all the code from class.customer.php to sales.customer.php and therefore the constructor in parent class set $name to "Jane". Here is the code: class.customer.php <?php class customer{ private $name; private $cust_no; public function __construct($customerid) { $this->name = 'Jane'; $this->cust_no = $customerid; } } ?> class.sales.php <?php require_once('class.customer.php'); class sales extends customer{ public function salesprint($customerid) { echo "Hello $this->name this is a print of your purchased products"; } } ?> testcustomer.php require_once('class.sales.php'); $objsales = new sales(17); $objsales->salesprint(17); ?> The Output I get Hello this is a print of your purchased products. What am i doing wrong ? thanks romesh

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  • DDD and MVC Models hold ID of separate entity or the entity itself?

    - by Dr. Zim
    If you have an Order that references a customer, does the model include the ID of the customer or a copy of the customer object like a value object (thinking DDD)? I would like to do ths: public class Order { public int ID {get;set;} public Customer customer {get;set;} ... } right now I do this: public class Order { public int ID {get;set;} public int customerID {get;set;} ... } It would be more convenient to include the complete customer object rather than an ID to the View Model passed to the form. Otherwise, I need to figure out how to get the vendor information to the view that the order references by ID. This also implies that the repository understand how to deal with the customer object that it finds within the order object when they call save (if we select the first option). If we select the second option, we will need to know where in the view model to put it. It is certain they will select an existing customer. However, it is also certain they may want to change the information in-place on the display form. One could argue to have the controller extract the customer object, submit customer changes separately to the repository, then submit changes to the order, keeping the customerID in the order.

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  • What is the purpose of unit testing an interface repository

    - by ahsteele
    I am unit testing an ICustomerRepository interface used for retrieving objects of type Customer. As a unit test what value am I gaining by testing the ICustomerRepository in this manner? Under what conditions would the below test fail? For tests of this nature is it advisable to do tests that I know should fail? i.e. look for id 4 when I know I've only placed 5 in the repository I am probably missing something obvious but it seems the integration tests of the class that implements ICustomerRepository will be of more value. [TestClass] public class CustomerTests : TestClassBase { private Customer SetUpCustomerForRepository() { return new Customer() { CustId = 5, DifId = "55", CustLookupName = "The Dude", LoginList = new[] { new Login { LoginCustId = 5, LoginName = "tdude" }, new Login { LoginCustId = 5, LoginName = "tdude2" } } }; } [TestMethod] public void CanGetCustomerById() { // arrange var customer = SetUpCustomerForRepository(); var repository = Stub<ICustomerRepository>(); // act repository.Stub(rep => rep.GetById(5)).Return(customer); // assert Assert.AreEqual(customer, repository.GetById(5)); } } Test Base Class public class TestClassBase { protected T Stub<T>() where T : class { return MockRepository.GenerateStub<T>(); } } ICustomerRepository and IRepository public interface ICustomerRepository : IRepository<Customer> { IList<Customer> FindCustomers(string q); Customer GetCustomerByDifID(string difId); Customer GetCustomerByLogin(string loginName); } public interface IRepository<T> { void Save(T entity); void Save(List<T> entity); bool Save(T entity, out string message); void Delete(T entity); T GetById(int id); ICollection<T> FindAll(); }

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  • Parallelism in .NET – Part 2, Simple Imperative Data Parallelism

    - by Reed
    In my discussion of Decomposition of the problem space, I mentioned that Data Decomposition is often the simplest abstraction to use when trying to parallelize a routine.  If a problem can be decomposed based off the data, we will often want to use what MSDN refers to as Data Parallelism as our strategy for implementing our routine.  The Task Parallel Library in .NET 4 makes implementing Data Parallelism, for most cases, very simple. Data Parallelism is the main technique we use to parallelize a routine which can be decomposed based off data.  Data Parallelism refers to taking a single collection of data, and having a single operation be performed concurrently on elements in the collection.  One side note here: Data Parallelism is also sometimes referred to as the Loop Parallelism Pattern or Loop-level Parallelism.  In general, for this series, I will try to use the terminology used in the MSDN Documentation for the Task Parallel Library.  This should make it easier to investigate these topics in more detail. Once we’ve determined we have a problem that, potentially, can be decomposed based on data, implementation using Data Parallelism in the TPL is quite simple.  Let’s take our example from the Data Decomposition discussion – a simple contrast stretching filter.  Here, we have a collection of data (pixels), and we need to run a simple operation on each element of the pixel.  Once we know the minimum and maximum values, we most likely would have some simple code like the following: for (int row=0; row < pixelData.GetUpperBound(0); ++row) { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } } .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; } This simple routine loops through a two dimensional array of pixelData, and calls the AdjustContrast routine on each pixel. As I mentioned, when you’re decomposing a problem space, most iteration statements are potentially candidates for data decomposition.  Here, we’re using two for loops – one looping through rows in the image, and a second nested loop iterating through the columns.  We then perform one, independent operation on each element based on those loop positions. This is a prime candidate – we have no shared data, no dependencies on anything but the pixel which we want to change.  Since we’re using a for loop, we can easily parallelize this using the Parallel.For method in the TPL: Parallel.For(0, pixelData.GetUpperBound(0), row => { for (int col=0; col < pixelData.GetUpperBound(1); ++col) { pixelData[row, col] = AdjustContrast(pixelData[row, col], minPixel, maxPixel); } }); Here, by simply changing our first for loop to a call to Parallel.For, we can parallelize this portion of our routine.  Parallel.For works, as do many methods in the TPL, by creating a delegate and using it as an argument to a method.  In this case, our for loop iteration block becomes a delegate creating via a lambda expression.  This lets you write code that, superficially, looks similar to the familiar for loop, but functions quite differently at runtime. We could easily do this to our second for loop as well, but that may not be a good idea.  There is a balance to be struck when writing parallel code.  We want to have enough work items to keep all of our processors busy, but the more we partition our data, the more overhead we introduce.  In this case, we have an image of data – most likely hundreds of pixels in both dimensions.  By just parallelizing our first loop, each row of pixels can be run as a single task.  With hundreds of rows of data, we are providing fine enough granularity to keep all of our processors busy. If we parallelize both loops, we’re potentially creating millions of independent tasks.  This introduces extra overhead with no extra gain, and will actually reduce our overall performance.  This leads to my first guideline when writing parallel code: Partition your problem into enough tasks to keep each processor busy throughout the operation, but not more than necessary to keep each processor busy. Also note that I parallelized the outer loop.  I could have just as easily partitioned the inner loop.  However, partitioning the inner loop would have led to many more discrete work items, each with a smaller amount of work (operate on one pixel instead of one row of pixels).  My second guideline when writing parallel code reflects this: Partition your problem in a way to place the most work possible into each task. This typically means, in practice, that you will want to parallelize the routine at the “highest” point possible in the routine, typically the outermost loop.  If you’re looking at parallelizing methods which call other methods, you’ll want to try to partition your work high up in the stack – as you get into lower level methods, the performance impact of parallelizing your routines may not overcome the overhead introduced. Parallel.For works great for situations where we know the number of elements we’re going to process in advance.  If we’re iterating through an IList<T> or an array, this is a typical approach.  However, there are other iteration statements common in C#.  In many situations, we’ll use foreach instead of a for loop.  This can be more understandable and easier to read, but also has the advantage of working with collections which only implement IEnumerable<T>, where we do not know the number of elements involved in advance. As an example, lets take the following situation.  Say we have a collection of Customers, and we want to iterate through each customer, check some information about the customer, and if a certain case is met, send an email to the customer and update our instance to reflect this change.  Normally, this might look something like: foreach(var customer in customers) { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } } Here, we’re doing a fair amount of work for each customer in our collection, but we don’t know how many customers exist.  If we assume that theStore.GetLastContact(customer) and theStore.EmailCustomer(customer) are both side-effect free, thread safe operations, we could parallelize this using Parallel.ForEach: Parallel.ForEach(customers, customer => { // Run some process that takes some time... DateTime lastContact = theStore.GetLastContact(customer); TimeSpan timeSinceContact = DateTime.Now - lastContact; // If it's been more than two weeks, send an email, and update... if (timeSinceContact.Days > 14) { theStore.EmailCustomer(customer); customer.LastEmailContact = DateTime.Now; } }); Just like Parallel.For, we rework our loop into a method call accepting a delegate created via a lambda expression.  This keeps our new code very similar to our original iteration statement, however, this will now execute in parallel.  The same guidelines apply with Parallel.ForEach as with Parallel.For. The other iteration statements, do and while, do not have direct equivalents in the Task Parallel Library.  These, however, are very easy to implement using Parallel.ForEach and the yield keyword. Most applications can benefit from implementing some form of Data Parallelism.  Iterating through collections and performing “work” is a very common pattern in nearly every application.  When the problem can be decomposed by data, we often can parallelize the workload by merely changing foreach statements to Parallel.ForEach method calls, and for loops to Parallel.For method calls.  Any time your program operates on a collection, and does a set of work on each item in the collection where that work is not dependent on other information, you very likely have an opportunity to parallelize your routine.

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