Search Results

Search found 23568 results on 943 pages for 'select'.

Page 131/943 | < Previous Page | 127 128 129 130 131 132 133 134 135 136 137 138  | Next Page >

• Multiple many-to-many JOINs in a single mysql query without Cartesian Product

  - by VWD

  At the moment I can get the results I need with two seperate SELECT statements SELECT COUNT(rl.refBiblioID) FROM biblioList bl LEFT JOIN refList rl ON bl.biblioID = rl.biblioID GROUP BY bl.biblioID SELECT GROUP_CONCAT( CONCAT_WS( ':', al.lastName, al.firstName ) ORDER BY al.authorID ) FROM biblioList bl LEFT JOIN biblio_author ba ON ba.biblioID = bl.biblioID JOIN authorList al ON al.authorID = ba.authorID GROUP BY bl.biblioID Combining them like this however SELECT GROUP_CONCAT( CONCAT_WS( ':', al.lastName, al.firstName ) ORDER BY al.authorID ), COUNT(rl.refBiblioID) FROM biblioList bl LEFT JOIN biblio_author ba ON ba.biblioID = bl.biblioID JOIN authorList al ON al.authorID = ba.authorID LEFT JOIN refList rl ON bl.biblioID = rl.biblioID GROUP BY bl.biblioID causes the author result column to have duplicate names. How can I get the desired results from one SELECT statement without using DISTINCT? With subqueries?

  Read the article

• Is there a way to optimize this update query?

  - by SchlaWiener

  I have a master table called "parent" and a related table called "childs" Now I run a query against the master table to update some values with the sum from the child table like this. UPDATE master m SET quantity1 = (SELECT SUM(quantity1) FROM childs c WHERE c.master_id = m.id), quantity2 = (SELECT SUM(quantity2) FROM childs c WHERE c.master_id = m.id), count = (SELECT COUNT(*) FROM childs c WHERE c.master_id = m.id) WHERE master_id = 666; Which works as expected but is not a good style because I basically make multiple SELECT querys on the same result. Is there a way to optimize that? (Making a query first and storing the values is not an option. I tried this: UPDATE master m SET (quantity1, quantity2, count) = ( SELECT SUM(quantity1), SUM(quantity2), COUNT(*) FROM childs c WHERE c.master_id = m.id ) WHERE master_id = 666; but that doesn't work.

  Read the article

• What useful macros have you created in Netbeans?

  - by Richard Poirier

  I use Netbeans (nightly build) for Ruby on Rails development and I'm looking to beef up my macros. I've created a few myself: copy identifier: select-identifier copy-to-clipboard paste clipboard over identifier: select-identifier paste-from-clipboard double quote element select-element-next "\"" single quote element: select-element-next "'" But I'm looking for other useful ones and Google is giving me nothing. The record macro feature usually doesn't work too well so I'd rather just "write" the macros myself but I can't even find a reference that lists what commands (like "select-identifier") are actually available. Any Netbeans macro gurus out there?

  Read the article

• Searching a table MySQL & PHP.

  - by S1syphus

  I want to be able to search through a MySQL table using values from a search string, from the url and display the results as an XML output. I think I have got the formatting and declaring the variables from the search string down. The issue I have is searching the entire table, I've looked over SO for previous answers, and they all seem to have to declare each column in the table to search through. So for example my database layout is as follows: **filesindex** -filename -creation -length -wall -playlocation First of all would the following be appropriate: $query = "SELECT * FROM filesindex WHERE filename LIKE '".$searchterm."%' UNION SELECT * FROM filesindex WHERE creation LIKE '".$searchterm."%' UNION SELECT * FROM filesindex WHERE length LIKE '".$searchterm."%' UNION SELECT * FROM filesindex WHERE wall LIKE '".$searchterm."%' UNION SELECT * FROM filesindex WHERE location LIKE '".$searchterm."%'"; Or ideally, is there an easier way that involves less hardcoding to search a table. Any ideas? Thanks

  Read the article

• Null Values And The T-SQL IN Operator

  - by Jesse

  I came across some unexpected behavior while troubleshooting a failing test the other day that took me long enough to figure out that I thought it was worth sharing here. I finally traced the failing test back to a SELECT statement in a stored procedure that was using the IN t-sql operator to exclude a certain set of values. Here’s a very simple example table to illustrate the issue: Customers CustomerId INT, NOT NULL, Primary Key CustomerName nvarchar(100) NOT NULL SalesRegionId INT NULL   The ‘SalesRegionId’ column contains a number representing the sales region that the customer belongs to. This column is nullable because new customers get created all the time but assigning them to sales regions is a process that is handled by a regional manager on a periodic basis. For the purposes of this example, the Customers table currently has the following rows: CustomerId CustomerName SalesRegionId 1 Customer A 1 2 Customer B NULL 3 Customer C 4 4 Customer D 2 5 Customer E 3   How could we write a query against this table for all customers that are NOT in sales regions 2 or 4? You might try something like this: 1: SELECT 2: CustomerId, 3: CustomerName, 4: SalesRegionId 5: FROM Customers 6: WHERE SalesRegionId NOT IN (2,4)   Will this work? In short, no; at least not in the way that you might expect. Here’s what this query will return given the example data we’re working with: CustomerId CustomerName SalesRegionId 1 Customer A 1 5 Customer E 5   I was expecting that this query would also return ‘Customer B’, since that customer has a NULL SalesRegionId. In my mind, having a customer with no sales region should be included in a set of customers that are not in sales regions 2 or 4.When I first started troubleshooting my issue I made note of the fact that this query should probably be re-written without the NOT IN clause, but I didn’t suspect that the NOT IN clause was actually the source of the issue. This particular query was only one minor piece in a much larger process that was being exercised via an automated integration test and I simply made a poor assumption that the NOT IN would work the way that I thought it should. So why doesn’t this work the way that I thought it should? From the MSDN documentation on the t-sql IN operator: If the value of test_expression is equal to any value returned by subquery or is equal to any expression from the comma-separated list, the result value is TRUE; otherwise, the result value is FALSE. Using NOT IN negates the subquery value or expression. The key phrase out of that quote is, “… is equal to any expression from the comma-separated list…”. The NULL SalesRegionId isn’t included in the NOT IN because of how NULL values are handled in equality comparisons. From the MSDN documentation on ANSI_NULLS: The SQL-92 standard requires that an equals (=) or not equal to (<>) comparison against a null value evaluates to FALSE. When SET ANSI_NULLS is ON, a SELECT statement using WHERE column_name = NULL returns zero rows even if there are null values in column_name. A SELECT statement using WHERE column_name <> NULL returns zero rows even if there are nonnull values in column_name. In fact, the MSDN documentation on the IN operator includes the following blurb about using NULL values in IN sub-queries or expressions that are used with the IN operator: Any null values returned by subquery or expression that are compared to test_expression using IN or NOT IN return UNKNOWN. Using null values in together with IN or NOT IN can produce unexpected results. If I were to include a ‘SET ANSI_NULLS OFF’ command right above my SELECT statement I would get ‘Customer B’ returned in the results, but that’s definitely not the right way to deal with this. We could re-write the query to explicitly include the NULL value in the WHERE clause: 1: SELECT 2: CustomerId, 3: CustomerName, 4: SalesRegionId 5: FROM Customers 6: WHERE (SalesRegionId NOT IN (2,4) OR SalesRegionId IS NULL)   This query works and properly includes ‘Customer B’ in the results, but I ultimately opted to re-write the query using a LEFT OUTER JOIN against a table variable containing all of the values that I wanted to exclude because, in my case, there could potentially be several hundred values to be excluded. If we were to apply the same refactoring to our simple sales region example we’d end up with: 1: DECLARE @regionsToIgnore TABLE (IgnoredRegionId INT) 2: INSERT @regionsToIgnore values (2),(4) 3:  4: SELECT 5: c.CustomerId, 6: c.CustomerName, 7: c.SalesRegionId 8: FROM Customers c 9: LEFT OUTER JOIN @regionsToIgnore r ON r.IgnoredRegionId = c.SalesRegionId 10: WHERE r.IgnoredRegionId IS NULL By performing a LEFT OUTER JOIN from Customers to the @regionsToIgnore table variable we can simply exclude any rows where the IgnoredRegionId is null, as those represent customers that DO NOT appear in the ignored regions list. This approach will likely perform better if the number of sales regions to ignore gets very large and it also will correctly include any customers that do not yet have a sales region.

  Read the article

• RadUpload problem with firefox

  - by just_name

  Q: I use RadUpload Telerik control to upload more than image ..this control is flexible and amazing one.. it works perfectly but recently i find the following problem :: the problem appears only in firefox not IE when click on Select button in this control to select my file the button doesn't work at all ,,but when i click on the textbox(which the file path appear in)it opens the window which i can select a file from it .. i don't know what is the problem with firefox .. i wanna the default behavior to not confuse the user ,i wanna when clicking on Select button , showing a window to select my file from it like IE.. any suggestions to fix this problem please...

  Read the article

• Help with grasping (INNER?) JOIN

  - by Greenie

  I'm having trouble building a query. I can do what I want in 3 different queries. SELECT id FROM table1 WHERE url LIKE '%/$downloadfile' put that in $url_id SELECT item_id FROM table2 WHERE rel_id = '$url_id'" put that in $item_id SELECT rel_id FROM table2 WHERE rel_id = '$item_id' AND field_id = '42'" put that in $user_id But from reading examples on joins and inner joins I think there's a more elegant way. I cant wrap my brain around writing a better query (but would like to) I can describe how it should go: table1 fields: id, url table2 fields item_id, rel_id, field_id I know the last part of table1.url (LIKE '%/$filename') with that I select table1.id. table1.id is equal to one entry in table2.rel_id. So get that and select the table2.item_id. In table2 there is another entry which has the same table2.item_id and it will have a table2.field_id = '42' And finally the value I need is the table2.rel_id where the table2.field_id was 42. I will fetch that value and put it in $user_id Can this be done with one query using joins/inner joins?

  Read the article

• How to avoid timestamp issue in a long query?

  - by pingi

  Hi, I have the following 2 tables: items: id int primary key bla text events: id_items int num int when timestamp without time zone ble text composite primary key: id_items, num and want to select to each item the most recent event (the newest 'when'). I wrote an request, but I don't know if it could be written more efficiently. Also on PostgreSQL there is a issue with comparing Timestamp objects: 2010-05-08T10:00:00.123 == 2010-05-08T10:00:00.321 so I select with 'MAX(num)' Any thoughts how to make it better? Thanks. SELECT i.*, ea.* FROM items AS i JOIN ( SELECT t.s AS t_s, t.c AS t_c, max(e.num) AS o FROM events AS e JOIN ( SELECT DISTINCT id_item AS s, MAX(when) AS c FROM events GROUP BY s ORDER BY c ) AS t ON t.s = e.id_item AND e.when = t.c GROUP BY t.s, t.c ) AS tt ON tt.t_s = i.id JOIN events AS ea ON ea.id_item = tt.t_s AND ea.cas = tt.t_c AND ea.num = tt.o;

  Read the article

• SQL server - climb up in the tree structure

  - by Vytas999

  Hello. I have some sql table, named Object, which saves tree data in fields ObjectID, ParentID, and others. I have implemented recurse procedure, which select everything down by objectID from tree, like this: 1. 1.1. 1.2. 1.2.1. ... Now o need to "Climb up" - by some ObjectID i need to select everything Up, like this: 1.2.1. 1.2. 1. How i can do that? In example, my "down" procedure looks like: ALTER PROCEDURE [dbo].[Object_SelectDownByRoot_Simple] @ObjectID int AS WITH tree (ObjectID, ParentID, ObjectName, ObjectCode) AS ( SELECT ObjectID, ParentID, ObjectName, ObjectCode FROM dbo.[ObjectQ] ofs WHERE( ObjectID = @ObjectID ) UNION ALL SELECT ofs.ObjectID, ofs.ParentID, ofs.ObjectName, ofs.ObjectCode FROM dbo.[ObjectQ] ofs JOIN tree ON tree.ObjectID = ofs.ParentID ) SELECT ObjectID, ParentID, ObjectName, ObjectCode FROM tree

  Read the article

• subqueries linq

  - by user297378

  Hey all I am trying to do a subquery in linq but the subquery is a value and it seems to not be working, can anyone help out? I am using the entit frame work I keep getting and int to string error not sure why. from lrp in remit.log_record_product join lr in remit.log_record on lrp.log_record_id equals lr.log_record_id where (lrp.que_submit_date >= RadDatePickerStartDate.SelectedDate) && (lrp.que_submit_date <= RadDatePickerEndDate.SelectedDate) select new { lrp.que_submit_date, lr.officer_name, lr.c_fname, lr.c_lname, lrp.price_sold, lrp.product_cost, gap_account_number = (from gap in remit.gap_contracts where gap.log_record_product_id == lrp.log_record_product_id select gap.account_number), iui_account_number = (from iui in remit.iui_contracts where iui.log_record_product_id == lrp.log_record_product_id select iui.account_number), dp_account_number = (from dp in remit.dp_contracts where dp.log_record_product_id == lrp.log_record_product_id select dp.account_number), mpd_account_number = (from mpd in remit.mbp_contracts where mpd.log_record_product_id == lrp.log_record_product_id select mpd.product_account_number) }

  Read the article

• Left Join Returning Extra Rows T-SQL?

  - by davemackey

  I have the following query: select * from ACADEMIC a left join RESIDENCY r on a.PEOPLE_CODE_ID = r.PEOPLE_CODE_ID where a.ACADEMIC_TERM='Fall' and r.ACADEMIC_TERM='Fall' and a.ACADEMIC_SESSION='' and a.ACADEMIC_YEAR = (Select Year(GetDate())) and r.ACADEMIC_YEAR = (Select Year(GetDate())) and (CLASS_LEVEL LIKE 'FR%' OR a.CLASS_LEVEL LIKE 'SO' OR a.CLASS_LEVEL LIKE 'JR' OR a.CLASS_LEVEL LIKE 'SR%') and r.RESIDENT_COMMUTER='R' For each person in the database it returns two rows with identical information. Yet, when I do the same query without the left join: select * from ACADEMIC a where a.ACADEMIC_TERM='Fall' and a.ACADEMIC_SESSION='' and a.ACADEMIC_YEAR = (Select Year(GetDate())) and (CLASS_LEVEL LIKE 'FR%' OR a.CLASS_LEVEL LIKE 'SO' OR a.CLASS_LEVEL LIKE 'JR' OR a.CLASS_LEVEL LIKE 'SR%') ORDER BY PEOPLE_ID It returns only one row for each person. I'm doing a left join - why is it adding an extra row? Shouldn't it only do that if I add a right join?

  Read the article

• SQL syntax problem (multiple selects)

  - by user279521

  I am having problems retrieving accurate data values with my stored proc query below: CREATE PROCEDURE usp_InvoiceErrorLog @RecID int AS DECLARE @ErrorString as varchar(1000), @ErrorCode as int; Select @ErrorCode = ErrorCode from tbl_AcctRecv_WebRpt Where RecID = @RecID; IF NOT(@ErrorCode = NULL) Begin Select @ErrorString = ErrorDesc from tbl_ErrDesc Where ErrorCode = @ErrorCode End Select RecID, VendorNum, VendorName, InvNum, InvTotal, (SELECT CONVERT(VARCHAR(11), InvDate, 106) AS [DD MON YYYY]) As InvDate, TicketRequestor, ErrorCode, @ErrorString as ErrorDesc from tbl_AcctRecv_WebRpt Where RecID = @RecID The ErrorDesc column (in the final select statement at the bottom) returns a NULL value, when it should return a valid string data. Any ideas?

  Read the article

• How can I load class's part using linq to sql without anonymous class or additional class?

  - by ais

  class Test { int Id{get;set;} string Name {get;set;} string Description {get;set;} } //1)ok context.Tests.Select(t => new {t.Id, t.Name}).ToList().Select(t => new Test{Id = t.Id, Name = t.Name}); //2)ok class TestPart{ int Id{get;set;} string Name {get;set;} } context.Tests.Select(t => new TestPart{Id = t.Id, Name = t.Name}).ToList().Select(t => new Test{Id = t.Id, Name = t.Name}); //3)error Explicit construction of entity type 'Test' in query is not allowed. context.Tests.Select(t => new Test{Id = t.Id, Name = t.Name}).ToList(); Is there any way to use third variant?

  Read the article

• Sql - add row when not existed

  - by Nguyen Tuan Linh

  Suppose I have a query that returns result like this: Project Year Type Amt PJ00001 2012 1 1000 PJ00001 2012 2 1000 PJ00001 2011 1 1000 PJ00002 2012 1 1000 What I want: Every Project will have 2 rows of Types for each Year. If the row is not there, add it to the result with Amt = 0. For example: - PJ00001 have 2 rows of type 1,2 in 2012 -- OK. But in 2011, it only have 1 row of Type 1 -- We add one row:PJ00001 2011 2 0 - PJ00002 have only 1 row of type 1 -- add:PJ00002 2012 2 0 Is there a way to easily do it. The only way I know now is to create a view like: PJ_VIEW. And then: SELECT * FROM PJ_VIEW UNION ALL SELECT t.PROJECT, t.YEAR_NO, 1 AS TYPE_NO, 0 AS AMT FROM PJ_VIEW t WHERE NOT EXISTS (SELECT 1 FROM PJ_VIEW t2 WHERE t2.PROJECT = t.PROJECT AND t2.YEAR_NO = t.YEAR_NO AND t2.TYPE_NO = 1) UNION ALL SELECT t.PROJECT, t.YEAR_NO, 2 AS TYPE_NO, 0 AS AMT FROM PJ_VIEW t WHERE NOT EXISTS (SELECT 1 FROM PJ_VIEW t2 WHERE t2.PROJECT = t.PROJECT AND t2.YEAR_NO = t.YEAR_NO AND t2.TYPE_NO = 2)

  Read the article

• How to loop over nodes with xmlfeed using scrapy python

  - by Kour ipm

  Hi i working on scrapy and trying xml feeds first time, below is my code class TestxmlItemSpider(XMLFeedSpider): name = "TestxmlItem" allowed_domains = {"http://www.nasinteractive.com"} start_urls = [ "http://www.nasinteractive.com/jobexport/advance/hcantexasexport.xml" ] iterator = 'iternodes' itertag = 'job' def parse_node(self, response, node): title = node.select('title/text()').extract() job_code = node.select('job-code/text()').extract() detail_url = node.select('detail-url/text()').extract() category = node.select('job-category/text()').extract() print title,";;;;;;;;;;;;;;;;;;;;;" print job_code,";;;;;;;;;;;;;;;;;;;;;" item = TestxmlItem() item['title'] = node.select('title/text()').extract() ....... return item result: File "/usr/lib/python2.7/site-packages/Scrapy-0.14.3-py2.7.egg/scrapy/item.py", line 56, in __setitem__ (self.__class__.__name__, key)) exceptions.KeyError: 'TestxmlItem does not support field: title' Totally there are 200+ items so i need to loop over and assign the node text to item but here all the results are displaying at once when we print, actually how can we loop over on nodes in scraping xml files with xmlfeedspider

  Read the article

• Exadata?????????INSERT?UPDATE

  - by Liu Maclean(???)

  Hybrid Columnar Compression??????Exadata?????????????,??????????(advanced compression)??,Hybrid columnar compression (HCC) ???Exadata????????HCC???????????CU(compression unit?????),??CU??????????,?????????????????????????,???CU????block??????????????? ???????INSERT/UPDATE??,??????????????,????UPDATE/INSERT???HCC?????????????????? hybrid columnar compression???????????????(bulk initial load)??,??????(direct load)??ALTER TABLE MOVE, IMPDP???????(append INSERT),??HCC??????????????????????? ???????????????????,?????????CU????????? ??????????????HCC?????????????for OLTP?????? ????????: SQL*Plus: Release 11.2.0.2.0 Production on Wed Sep 12 06:14:53 2012 Copyright (c) 1982, 2010, Oracle. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - Production With the Partitioning, Automatic Storage Management, OLAP, Data Mining and Real Application Testing options SQL> grant dba to scott; Grant succeeded. SQL> conn scott/oracle Connected. SQL> SQL> create table hcc_maclean tablespace users compress for query high as select * from dba_objects; Table created. 1* select rowid,owner,object_name,dbms_rowid.rowid_block_number(rowid) from hcc_maclean where owner='MACLEAN' SQL> / ROWID OWNER OBJECT_NAME DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID) ------------------------------ ------------------------------ -------------------- ------------------------------------ AAAThuAAEAAAHTJAOI MACLEAN SALES 29897 AAAThuAAEAAAHTJAOJ MACLEAN MYCUSTOMERS 29897 AAAThuAAEAAAHTJAOK MACLEAN MYCUST_ARCHIVE 29897 AAAThuAAEAAAHTJAOL MACLEAN MYCUST_QUERY 29897 AAAThuAAEAAAHTJAOh MACLEAN COMPRESS_QUERY 29897 AAAThuAAEAAAHTJAOi MACLEAN UNCOMPRESS 29897 AAAThuAAEAAAHTJAOj MACLEAN CHAINED_ROWS 29897 AAAThuAAEAAAHTJAOk MACLEAN COMPRESS_QUERY1 29897 8 rows selected. select dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_relative_fno(rowid) from hcc_maclean where owner='MACLEAN'; session A: update hcc_maclean set OBJECT_NAME=OBJECT_NAME||'DBM' where rowid='AAAThuAAEAAAHTJAOI'; session B: update hcc_maclean set OBJECT_NAME=OBJECT_NAME||'DBM' where rowid='AAAThuAAEAAAHTJAOJ'; SQL> select sid,wait_event_text,BLOCKER_SID from v$wait_chains; SID WAIT_EVENT_TEXT BLOCKER_SID ---------- ---------------------------------------------------------------- ----------- 13 enq: TX - row lock contention 136 136 SQL*Net message from client ????session A block B,????HCC???update row??CU?????CU?????? SQL> alter system checkpoint; System altered. SQL> / System altered. SQL> alter system dump datafile 4 block 29897 2 ; Block header dump: 0x010074c9 Object id on Block? Y seg/obj: 0x1386e csc: 0x00.1cad7e itc: 3 flg: E typ: 1 - DATA brn: 0 bdba: 0x10074c8 ver: 0x01 opc: 0 inc: 0 exflg: 0 Itl Xid Uba Flag Lck Scn/Fsc 0x01 0xffff.000.00000000 0x00000000.0000.00 C--- 0 scn 0x0000.001cabfa 0x02 0x000a.00a.00000430 0x00c051a7.0169.17 ---- 1 fsc 0x0000.00000000 0x03 0x0000.000.00000000 0x00000000.0000.00 ---- 0 fsc 0x0000.00000000 avsp=0x14 tosp=0x14 r0_9ir2=0x0 mec_kdbh9ir2=0x0 76543210 shcf_kdbh9ir2=---------- 76543210 flag_9ir2=--R----- Archive compression: Y fcls_9ir2[0]={ } 0x16:pti[0] nrow=1 offs=0 0x1a:pri[0] offs=0x30 block_row_dump: tab 0, row 0, @0x30 tl: 8016 fb: --H-F--N lb: 0x2 cc: 1 ==>??CU??ITL 0x02 nrid: 0x010074ca.0 col 0: [8004] Compression level: 02 (Query High) Length of CU row: 8004 kdzhrh: ------PC CBLK: 1 Start Slot: 00 NUMP: 01 PNUM: 00 POFF: 7984 PRID: 0x010074ca.0 CU header: CU version: 0 CU magic number: 0x4b445a30 CU checksum: 0xf8faf86e CU total length: 8694 CU flags: NC-U-CRD-OP ncols: 15 nrows: 995 algo: 0 CU decomp length: 8487 len/value length: 100111 row pieces per row: 1 num deleted rows: 1 deleted rows: 904, START_CU: ????????????row?????: SQL> select DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN','AAAThuAAEAAAHTJAOk') from dual; DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN','AAATHUAAEAAAHTJAOK' -------------------------------------------------------------------------------- 4 COMP_NOCOMPRESS CONSTANT NUMBER := 1;COMP_FOR_OLTP CONSTANT NUMBER := 2;COMP_FOR_QUERY_HIGH CONSTANT NUMBER := 4;COMP_FOR_QUERY_LOW CONSTANT NUMBER := 8;COMP_FOR_ARCHIVE_HIGH CONSTANT NUMBER := 16;COMP_FOR_ARCHIVE_LOW CONSTANT NUMBER := 32; COMP_RATIO_MINROWS CONSTANT NUMBER := 1000000;COMP_RATIO_ALLROWS CONSTANT NUMBER := -1; ?????????????,??COMP_FOR_QUERY_HIGH?4,COMP_FOR_QUERY_LOW ?8 ?????????GET_COMPRESSION_TYPE??rowid????????4?????COMP_FOR_QUERY_HIGH????: SQL> update hcc_maclean set OBJECT_NAME=OBJECT_NAME||'DBM' where owner='MACLEAN'; 8 rows updated. SQL> commit; Commit complete. SQL> select DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN',rowid) from HCC_MACLEAN where owner='MACLEAN'; DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN',ROWID) ------------------------------------------------------------------ 1 1 1 1 1 1 1 1 8 rows selected. ??????????????COMPRESSION_TYPE?COMP_FOR_QUERY_HIGH???COMP_NOCOMPRESS,????????compress for query high????????????????? ?11g????????????????????HCC??????????? ALTER TABLE MOVE???????????????????HCC??? SQL> ALTER TABLE hcc_MACLEAN move COMPRESS FOR ARCHIVE HIGH; Table altered. SQL> select DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN',rowid) from HCC_MACLEAN where owner='MACLEAN'; DBMS_COMPRESSION.GET_COMPRESSION_TYPE('SCOTT','HCC_MACLEAN',ROWID) ------------------------------------------------------------------ 16 16 16 16 16 16 16 16 8 rows selected.

  Read the article

• Problem with graphiz on Unix

  - by J3n

  When I'm on Unix, my graphs with graphphiz are less nice. The tail or the head of the edge is not always linked to the boundary of the port. You can see the result here : http://www.freeimagehosting.net/image.php?59d8eb4b30.jpg <xsl:value-of select="$source"/>:<xsl:value-of select="$prot"/> -&gt; <xsl:value-of select="$destination"/>:<xsl:value-of select="$prot"/>[color="black",label="<xsl:value-of select="$prot"/>",fontcolor="black",tailclip=true,headclip=true];

  Read the article

• Joining on NULLs

  - by Dave Ballantyne

  A problem I see on a fairly regular basis is that of dealing with NULL values.  Specifically here, where we are joining two tables on two columns, one of which is ‘optional’ ie is nullable.  So something like this: i.e. Lookup where all the columns are equal, even when NULL.   NULL’s are a tricky thing to initially wrap your mind around.  Statements like “NULL is not equal to NULL and neither is it not not equal to NULL, it’s NULL” can cause a serious brain freeze and leave you a gibbering wreck and needing your mummy. Before we plod on, time to setup some data to demo against. Create table #SourceTable ( Id integer not null, SubId integer null, AnotherCol char(255) not null ) go create unique clustered index idxSourceTable on #SourceTable(id,subID) go with cteNums as ( select top(1000) number from master..spt_values where type ='P' ) insert into #SourceTable select Num1.number,nullif(Num2.number,0),'SomeJunk' from cteNums num1 cross join cteNums num2 go Create table #LookupTable ( Id integer not null, SubID integer null ) go insert into #LookupTable Select top(100) id,subid from #SourceTable where subid is not null order by newid() go insert into #LookupTable Select top(3) id,subid from #SourceTable where subid is null order by newid() If that has run correctly, you will have 1 million rows in #SourceTable and 103 rows in #LookupTable.  We now want to join one to the other. First attempt – Lets just join select * from #SourceTable join #LookupTable on #LookupTable.id = #SourceTable.id and #LookupTable.SubID = #SourceTable.SubID OK, that’s a fail.  We had 100 rows back,  we didn’t correctly account for the 3 rows that have null values.  Remember NULL <> NULL and the join clause specifies SUBID=SUBID, which for those rows is not true. Second attempt – Lets deal with those pesky NULLS select * from #SourceTable join #LookupTable on #LookupTable.id = #SourceTable.id and isnull(#LookupTable.SubID,0) = isnull(#SourceTable.SubID,0) OK, that’s the right result, well done and 99.9% of the time that is where its left. It is a relatively trivial CPU overhead to wrap ISNULL around both columns and compare that result, so no problems.  But, although that’s true, this a relational database we are using here, not a procedural language.  SQL is a declarative language, we are making a request to the engine to get the results we want.  How we ask for them can make a ton of difference. Lets look at the plan for our second attempt, specifically the clustered index seek on the #SourceTable   There are 2 predicates. The ‘seek predicate’ and ‘predicate’.  The ‘seek predicate’ describes how SQLServer has been able to use an Index.  Here, it has been able to navigate the index to resolve where ID=ID.  So far so good, but what about the ‘predicate’ (aka residual probe) ? This is a row-by-row operation.  For each row found in the index matching the Seek Predicate, the leaf level nodes have been scanned and tested using this logical condition.  In this example [Expr1007] is the result of the IsNull operation on #LookupTable and that is tested for equality with the IsNull operation on #SourceTable.  This residual probe is quite a high overhead, if we can express our statement slightly differently to take full advantage of the index and make the test part of the ‘Seek Predicate’. Third attempt – X is null and Y is null So, lets state the query in a slightly manner: select * from #SourceTable join #LookupTable on #LookupTable.id = #SourceTable.id and ( #LookupTable.SubID = #SourceTable.SubID or (#LookupTable.SubID is null and #SourceTable.SubId is null) ) So its slightly wordier and may not be as clear in its intent to the human reader, that is what comments are for, but the key point is that it is now clearer to the query optimizer what our intention is. Let look at the plan for that query, again specifically the index seek operation on #SourceTable No ‘predicate’, just a ‘Seek Predicate’ against the index to resolve both ID and SubID.  A subtle difference that can be easily overlooked.  But has it made a difference to the performance ? Well, yes , a perhaps surprisingly high one. Clever query optimizer well done. If you are using a scalar function on a column, you a pretty much guaranteeing that a residual probe will be used.  By re-wording the query you may well be able to avoid this and use the index completely to resolve lookups. In-terms of performance and scalability your system will be in a much better position if you can.

  Read the article

• [JS/jQuery] Using argument (this) passed via element eventhandler

  - by Kel

  Hey guys, I want to use the argument I pass (this) in a JS function and treat it as an jQuery variable. Example: <script> function useMe(obj){ $(obj).val(); ... ... ... } </script> <select id="selectid" onChange="useMe(this)"> <option>......</option> </select> Is there a possibility to treat the passed argument as a jQuery element? Btw. I need to do it this way, because the select-element isn't created on load. The select element will be created later asynchronously. So, this won't work: $("select").each(function (i){ var select_id = $(this).attr("id"); $(this).change(function(e){ because it doesn't exist yet. Thanks for your help.

  Read the article

• Using IF in T-SQL weakens or breaks execution plan caching?

  - by AnthonyWJones

  It has been suggest to me that the use of IF statements in t-SQL batches is detrimental to performance. I'm trying to find some confirmation of this assertion. I'm using SQL Server 2005 and 2008. The assertion is that with the following batch:- IF @parameter = 0 BEGIN SELECT ... something END ELSE BEGIN SELECT ... something else END SQL Server cannot re-use the execution plan generated because the next execution may need a different branch. This implies that SQL Server will eliminate one branch entirely from execution plan on the basis that for the current execution it can already determine which branch is needed. Is this really true? In addition what happens in this case:- IF EXISTS (SELECT ....) BEGIN SELECT ... something END ELSE BEGIN SELECT ... something else END where it's not possible to determine in advance which branch will be executed?

  Read the article

• MSSQL "for xml", multiple tables, multiple nodes

  - by Nelson

  Is it possible to select multiple tables at once? For example, I can do: SELECT ( SELECT * FROM Articles FOR XML PATH('article'), TYPE ) FOR XML PATH('articles'), ROOT('data') and SELECT ( SELECT * FROM ArticleTypes FOR XML PATH('articleType'), TYPE ) FOR XML PATH('articleTypes'), ROOT('data') Can I join both so that I get the following output? I can't use UNION because the table structures don't match. <data> <articles> <article>...</article> ... </articles> <articleTypes> <articleType>...</articleType> ... </articleTypes> </data>

  Read the article

• Eliminate subquery for average numeric value

  - by Dave Jarvis

  Quest A query selects locations that begin with Vancouver, which are in a 5 minute radius from one another. SQL Code The following SQL abomination does the trick: SELECT NAME FROM STATION WHERE DISTRICT_ID = '110' AND NAME LIKE 'Vancouver%' AND LATITUDE BETWEEN (SELECT round((min(LATITUDE) + max(LATITUDE)) / 2)-5 FROM STATION WHERE DISTRICT_ID = '110' AND NAME LIKE 'Vancouver%') and (SELECT round((min(LATITUDE) + max(LATITUDE)) / 2)+5 FROM STATION WHERE DISTRICT_ID = '110' AND NAME LIKE 'Vancouver%') AND LONGITUDE BETWEEN (SELECT round((min(LONGITUDE) + max(LONGITUDE)) / 2)-5 FROM STATION WHERE DISTRICT_ID = '110' AND NAME LIKE 'Vancouver%') and (SELECT round((min(LONGITUDE) + max(LONGITUDE)) / 2)+5 FROM STATION WHERE DISTRICT_ID = '110' AND NAME LIKE 'Vancouver%') ORDER BY LATITUDE Question How can this query be simplified to remove the redundancy, without using a view? Restrictions The database is MySQL, but ANSI SQL is always nice. Thank you!

  Read the article

• Watir question regarding selecting a hidden dropdown.

  - by AJ

  Hi, I have two dropdowns, the second dropdown does not show until a choice is made from the first one. Using watir, i can select the first dropdown, and when i watch it, the second one becomes active, but it cannot select it. i just tried the regular select_list using name and id. Here is the code for the second drop down. <td> <input type="hidden" value="1" name="list" id="list"> <script type="text/JavaScript" language="JavaScript"></script> <select> <option value="">1</option> <option value="2">2</option> <option value="3">3</option> </select> </td> I've also notice the value for the hidden field change as i select different options. Thanks for any help

  Read the article

• How to optimize an SQL query with many thousands of WHERE clauses

  - by bugaboo

  I have a series of queries against a very mega large database, and I have hundreds-of-thousands of ORs in WHERE clauses. What is the best and easiest way to optimize such SQL queries? I found some articles about creating temporary tables and using joins, but I am unsure. I'm new to serious SQL, and have been cutting and pasting results from one into the next. SELECT doc_id, language, author, title FROM doc_text WHERE language='fr' OR language='es' SELECT doc_id, ref_id FROM doc_ref WHERE doc_id=1234567 OR doc_id=1234570 OR doc_id=1234572 OR doc_id=1234596 OR OR OR ... SELECT ref_id, location_id FROM ref_master WHERE ref_id=098765 OR ref_id=987654 OR ref_id=876543 OR OR OR ... SELECT location_id, location_display_name FROM location SELECT doc_id, index_code, FROM doc_index WHERE doc_id=1234567 OR doc_id=1234570 OR doc_id=1234572 OR doc_id=1234596 OR OR OR x100,000 These unoptimized query can take over 24 hours each. Cheers.

  Read the article

• Whats wrong with my SQL query?

  - by William

  I'm trying to set up a query that shows the first post of each thread and is ordered by the date of the last post in each thread. I got the first part down with this query: SELECT * FROM ( SELECT Min( ID ) AS MinID FROM test_posts GROUP BY Thread )tmin JOIN test_posts ON test_posts.ID = tmin.MinID Now I need to figure out how to call the last post of each thread into a table, than use that table to order the first tables results. So far I got this, but it doesn't work. SELECT * FROM ( SELECT Min( ID ) AS MinID FROM test_posts GROUP BY Thread )tmin JOIN test_posts ON test_posts.ID = tmin.MinID ORDER BY (SELECT MAX( ID ) AS MaxID, Thread, MAX( Date ) FROM test_posts GROUP BY Thread )tmax tmax.Date

  Read the article

< Previous Page | 127 128 129 130 131 132 133 134 135 136 137 138  | Next Page >