Search Results

Search found 100454 results on 4019 pages for 'sql server 2011'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 488/4019 | < Previous Page | 484 485 486 487 488 489 490 491 492 493 494 495  | Next Page >

  • MS SQL Database with clustered GUID PKs - switch clustered index or switch to sequential (comb) GUID

    - by Eyvind
    We have a database in which all the PKs are GUIDs, and most of the PKs are also the clustered index for the table. We know that this is bad (due to the random nature of GUIDs). So, it seems there are basically two options here (short of throwing out GUIDs as PKs altogether, which we cannot do (at least not at this time)). We could change the GUID generation algorithm to e.g. the one that NHibernate uses, as detailed in this post, or we could, for the tables that are under the heaviest use, change to a different clustered index, e.g. an IDENTITY column, and keep the "random" GUIDs as PKs. Is it possible to give any general recommendations in such a scenario? The application in question has 500+ tables, the largest one presently at about 1,5 million rows, a few tables around 500 000 rows, and the rest significantly lower (most of them well below 10K). Furthermore, the application is installed at several customer sites already, so we have to take any possible negative effects for existing customer into consideration. Thanks!

    Read the article

  • Don't Understand Sql Server Error

    - by Jonathan Wood
    I have a table of users (User), and need to create a new table to track which users have referred other users. So, basically, I'm creating a many-to-many relation between rows in the same table. So I'm trying to create table UserReferrals with the columns UserId and UserReferredId. I made both columns a compound primary key. And both columns are foreign keys that link to User.UserID. Since deleting a user should also delete the relationship, I set both foreign keys to cascade deletes. When the user is deleted, any related rows in UserReferrals should also delete. But this gives me the message: 'User' table saved successfully 'UserReferrals' table Unable to create relationship 'FK_UserReferrals_User'. Introducing FOREIGN KEY constraint 'FK_UserReferrals_User' on table 'UserReferrals' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint. See previous errors. I don't get this error. A cascading delete only deletes the row with the foreign key, right? So how can it cause "cycling cascade paths"? Thanks for any tips.

    Read the article

  • Linq To Sql - DataContext.SubmitChanges() problem

    - by Ahmet Altun
    I have a code like this. DBContext is Datacontext instance. try { TBLORGANISM org = new TBLORGANISM(); org.OrganismDesc = p.Subject; DBContext.TBLORGANISMs.InsertOnSubmit(org); DBContext.SubmitChanges(); } catch (Exception) { } At this point, I want to IGNORE the error and want to be skipped. Not to be retried. But when I try another insert like TBLACTION act = new TBLACTION(); act.ActionDesc = p.ActionName; DBContext.TBLACTIONs.InsertOnSubmit(act); DBContext.SubmitChanges(); SubmitChanges firstly retries previous attempt. How can I tell "skip errors, don't try again"?

    Read the article

  • Show SQL query results in Sharepoint

    - by JoeOD
    Hi All I support Rational clearquest for my company and have been asked to show some of the data in Sharepoint. I can query the data in Clearquest no problem (Using Toad) but have no idea about how to go displaying it in Sharepoint. The data I'm querying contains dates and ideally I'd like to be able display it in a sharepoint calendar but list format would do for the moment. Can anybody offer advice on even where to start? Thanks, Joe

    Read the article

  • Sql Query - Selecting rows where user can be both friend and user

    - by Gublooo
    Hey Sorry the title is not very clear. This is a follow up to my earlier question where one of the members helped me with a query. I have a following friends Table Friend friend_id - primary key user_id user_id_friend status The way the table is populated is - when I send a friend request to John - my userID appears in user_id and Johns userID appears in user_id_friend. Now another scenario is say Mike sends me a friend request - in this case mike's userID will appear in user_id and my userID will appear in user_id_friend So to find all my friends - I need to run a query to find where my userID appears in both user_id column as well as user_id_friend column What I am trying to do now is - when I search for user say John - I want all users Johns listed on my site to show up along with the status of whether they are my friend or not and if they are not - then show a "Add Friend" button. Based on the previous post - I got this query which does part of the job - My example user_id is 1: SELECT u.user_id, f.status FROM user u LEFT OUTER JOIN friend f ON f.user_id = u.user_id and f.user_id_friend = 1 where u.name like '%' So this only shows users with whom I am friends where they have sent me request ie my userID appears in user_id_friend. Although I am friends with others (where my userID appears in user_id column) - this query will return that as null To get those I need another query like this SELECT u.user_id, f.status FROM user u LEFT OUTER JOIN friend f ON f.user_id_friend = u.user_id and f.user_id = 1 where u.name like '%' So how do I combine these queries to return 1 set of users and what my friendship status with them is. I hope my question is clear Thanks

    Read the article

  • Sql order by within a group by with aggregate

    - by NG
    Say I have Team/Name/Some number Cardinals Jason 8 Cardinals Chris 5 Yankees Joba 6 Cubs Carlos 6 Cardinals Chris 6 And I want Cardinals Jason 8 Cardinals Chris 11 Cubs Carlos 6 Yankees Joba 6 So, what I'm doing is grouping by team, grouping by name, summing by some number However, within cardinals I want to make sure the names are in a particular order. If I just do an "order by name desc" for example then the the whole grouping gets ignored. So how can I order within a group.

    Read the article

  • Saving a select count(*) value to an integer (SQL Server)

    - by larryq
    Hi everyone, I'm having some trouble with this statement, owing no doubt to my ignorance of what is returned from this select statement: declare @myInt as INT set @myInt = (select COUNT(*) from myTable as count) if(@myInt <> 0) begin print 'there's something in the table' end There are records in myTable, but when I run the code above the print statement is never run. Further checks show that myInt is in fact zero after the assignment above. I'm sure I'm missing something, but I assumed that a select count would return a scalar that I could use above?

    Read the article

  • SQL DATEDIFF Not working!?

    - by James
    Hi all, I am running a simple DATEDIFF query but it doesn't seem to calculate the days properly or i'm doing something wrong. If I run PRINT DATEDIFF(Day, 2010-01-20, 2010-01-01) RETURN 19 Which is correct. If i change the month in the first date to Feb (02) I get something strange. PRINT DATEDIFF(Day, 2010-02-20, 2010-01-01) RETURN 20 Now shouldn't it be 48 or something? Can anyone see what i'm doing wrong or is this not the correct function to be using if I want the No of days between these dates? I've tried taking one date from the other: PRINT (2010-02-20) - (2010-01-01) RETURN -20 Any help much appreciated. Thanks J.

    Read the article

  • SQL Server: Difference between PARTITION BY and GROUP BY

    - by Mike Mooney
    I've been using GROUP BY for all types of aggregate queries over the years. Recently, I've been reverse-engineering some code that uses PARTITION BY to perform aggregations. In reading through all the documentation I can find about PARTITION BY, it sounds a lot like GROUP BY, maybe with a little extra functionality added in? Are they two versions of the same general functionality, or are they something different entirely?

    Read the article

  • LINQ(2 SQL) Insert Multiple Tables Question

    - by Refracted Paladin
    I have 3 tables. A primary EmploymentPlan table with PK GUID EmploymentPlanID and 2 FK's GUID PrevocServicesID & GUID JobDevelopmentServicesID. There are of course other fields, almost exclusively varchar(). Then the 2 secondary tables with the corresponding PK to the primary's FK's. I am trying to write the LINQ INSERT Method and am struggling with the creation of the keys. Say I have a method like below. Is that correct? Will that even work? Should I have seperate methods for each? Also, when INSERTING I didn't think I needed to provide the PK for a table. It is auto-generated, no? Thanks, public static void InsertEmploymentPlan(int planID, Guid employmentQuestionnaireID, string user, bool communityJob, bool jobDevelopmentServices, bool prevocServices, bool transitionedPrevocIntegrated, bool empServiceMatchPref) { using (var context = MatrixDataContext.Create()) { var empPrevocID = Guid.NewGuid(); var prevocPlan = new tblEmploymentPrevocService { EmploymentPrevocID = empPrevocID }; context.tblEmploymentPrevocServices.InsertOnSubmit(prevocPlan); var empJobDevID = Guid.NewGuid(); var jobDevPlan = new tblEmploymentJobDevelopmetService() { JobDevelopmentServicesID = empJobDevID }; context.tblEmploymentJobDevelopmetServices.InsertOnSubmit(jobDevPlan); var empPlan = new tblEmploymentQuestionnaire { CommunityJob = communityJob, EmploymentQuestionnaireID = Guid.NewGuid(), InsertDate = DateTime.Now, InsertUser = user, JobDevelopmentServices = jobDevelopmentServices, JobDevelopmentServicesID =empJobDevID, PrevocServices = prevocServices, PrevocServicesID =empPrevocID, TransitionedPrevocToIntegrated =transitionedPrevocIntegrated, EmploymentServiceMatchPref = empServiceMatchPref }; context.tblEmploymentQuestionnaires.InsertOnSubmit(empPlan); context.SubmitChanges(); } } I understand I can use more then 1 InsertOnSubmit, See SO ? HERE, I just don't understand how that would apply to my situation and the PK/FK creation.

    Read the article

  • For Nvarchar(Max) I am only getting 4000 characters in TSQL?

    - by Malcolm
    Hi, This is for SS 2005. Why I am i only getting 4000 characters and not 8000? It truncates the string @SQL1 at 4000. ALTER PROCEDURE sp_AlloctionReport( @where NVARCHAR(1000), @alldate NVARCHAR(200), @alldateprevweek NVARCHAR(200)) AS DECLARE @SQL1 NVARCHAR(Max) SET @SQL1 = 'SELECT DISTINCT VenueInfo.VenueID, VenueInfo.VenueName, VenuePanels.PanelID, VenueInfo.CompanyName, VenuePanels.ProductCode, VenuePanels.MF, VenueInfo.Address1, VenueInfo.Address2, '' As AllocationDate, '' As AbbreviationCode, VenueInfo.Suburb, VenueInfo.Route, VenueInfo.ContactFirstName, VenueInfo.ContactLastName, VenueInfo.SuitableTime, VenueInfo.OldVenueName, VenueCategories.Category, VenueInfo.Phone, VenuePanels.Location, VenuePanels.Comment, [VenueCategories].[Category] + '' Allocations'' AS ReportHeader, ljs.AbbreviationCode AS PrevWeekCampaign FROM (((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID = VenuePanels.VenueID) INNER JOIN VenueCategories ON VenueInfo.CategoryID = VenueCategories.CategoryID) LEFT JOIN (SELECT CampaignProductions.AbbreviationCode, VenuePanels.PanelID, CampaignAllocations.AllocationDate FROM (((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID=VenuePanels.VenueID) INNER JOIN CampaignAllocations ON VenuePanels.PanelID=CampaignAllocations.PanelID) INNER JOIN CampaignProductions ON CampaignAllocations.CampaignID=CampaignProductions.CampaignID) INNER JOIN VenueCategories ON VenueInfo.CategoryID=VenueCategories.CategoryID WHERE ' + @alldateprevweek + ') ljs ON VenuePanels.PanelID = ljs.PanelID) INNER JOIN (SELECT VenueInfo.VenueID, VenuePanels.PanelID, VenueInfo.VenueName, VenueInfo.CompanyName, VenuePanels.ProductCode, VenuePanels.MF, VenueInfo.Address1, VenueInfo.Address2, CampaignAllocations.AllocationDate, CampaignProductions.AbbreviationCode, VenueInfo.Suburb, VenueInfo.Route, VenueInfo.ContactFirstName, VenueInfo.ContactLastName, VenueInfo.SuitableTime, VenueInfo.OldVenueName, VenueCategories.Category, VenueInfo.Phone, VenuePanels.Location, VenuePanels.Comment, [Category] + '' Allocations'' AS ReportHeader, ljs2.AbbreviationCode AS PrevWeekCampaign FROM ((((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID = VenuePanels.VenueID) INNER JOIN CampaignAllocations ON VenuePanels.PanelID = CampaignAllocations.PanelID) INNER JOIN CampaignProductions ON CampaignAllocations.CampaignID = CampaignProductions.CampaignID) INNER JOIN VenueCategories ON VenueInfo.CategoryID = VenueCategories.CategoryID) LEFT JOIN (SELECT CampaignProductions.AbbreviationCode, VenuePanels.PanelID, CampaignAllocations.AllocationDate FROM (((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID=VenuePanels.VenueID) INNER JOIN CampaignAllocations ON VenuePanels.PanelID=CampaignAllocations.PanelID) INNER JOIN CampaignProductions ON CampaignAllocations.CampaignID=CampaignProductions.CampaignID) INNER JOIN VenueCategories ON VenueInfo.CategoryID=VenueCategories.CategoryID WHERE ' + @alldateprevweek + ') ljs2 ON VenuePanels.PanelID = ljs2.PanelID WHERE ' + @alldate + ' AND ' + @where + ') ljs3 ON VenueInfo.VenueID = ljs3.VenueID WHERE (((VenuePanels.PanelID)<>ljs3.[PanelID] And (VenuePanels.PanelID) Not In (SELECT PanelID FROM CampaignAllocations WHERE ' + @alldateprevweek + ')) AND ' + @where + ') UNION ALL SELECT VenueInfo.VenueID, VenueInfo.VenueName, VenuePanels.PanelID, VenueInfo.CompanyName, VenuePanels.ProductCode, VenuePanels.MF, VenueInfo.Address1, VenueInfo.Address2, CampaignAllocations.AllocationDate, CampaignProductions.AbbreviationCode, VenueInfo.Suburb, VenueInfo.Route, VenueInfo.ContactFirstName, VenueInfo.ContactLastName, VenueInfo.SuitableTime, VenueInfo.OldVenueName, VenueCategories.Category, VenueInfo.Phone, VenuePanels.Location, VenuePanels.Comment, [Category] + '' Allocations'' AS ReportHeader, ljs.AbbreviationCode AS PrevWeekCampaign FROM ((((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID = VenuePanels.VenueID) INNER JOIN CampaignAllocations ON VenuePanels.PanelID = CampaignAllocations.PanelID) INNER JOIN CampaignProductions ON CampaignAllocations.CampaignID = CampaignProductions.CampaignID) INNER JOIN VenueCategories ON VenueInfo.CategoryID = VenueCategories.CategoryID) LEFT JOIN (SELECT CampaignProductions.AbbreviationCode, VenuePanels.PanelID, CampaignAllocations.AllocationDate FROM (((VenueInfo INNER JOIN VenuePanels ON VenueInfo.VenueID=VenuePanels.VenueID) INNER JOIN CampaignAllocations ON VenuePanels.PanelID=CampaignAllocations.PanelID) INNER JOIN CampaignProductions ON CampaignAllocations.CampaignID=CampaignProductions.CampaignID) INNER JOIN VenueCategories ON VenueInfo.CategoryID=VenueCategories.CategoryID WHERE ' + @alldateprevweek + ') ljs ON VenuePanels.PanelID = ljs.PanelID WHERE ' + @alldate + ' AND ' + @where Select @SQL1

    Read the article

  • LINQ to SQL: filter nested objects with soft deletes

    - by Alex
    Hello everyone, I'm using soft deleting in my database (IsDeleted field). I'm actively using LoadWith and AssociateWith methods to retrieve and filter nested records. The thing is AssociateWith only works with properties that represents a one-to-many relationship. DataLoadOptions loadOptions = new DataLoadOptions(); loadOption.LoadWith<User>(u = > u.Roles); loadOption.AssociateWith<User>(u = > u.Roles.Where(r = > !r.IsDeleted)); In the example above I just say: I want to retrieve users with related (undeleted) roles. But when I have one-to-one relationship, e.g. Document - File (the only one file is related to the document) I'm unable to filter soft deleted object: DataLoadOptions loadOptions = new DataLoadOptions(); loadOption.LoadWith<Document>(d = > d.File); // the next certainly won't work loadOption.AssociateWith<File>(f = > !f.IsDeleted); So, is there any idea how to filter records within the one-to-one relationship? Thanks!

    Read the article

  • sql group by with left join

    - by cometta
    fail statement:Error: ORA-00979: not a GROUP BY expression select org_division.name , org_department.name , org_surveylog.division_code as divisionCode,org_surveylog.department_code as departmentCode , max(org_surveylog.actiondate) from org_surveylog left join org_division on (org_surveylog.division_code= org_division.division_code and org_surveylog.SURVEY_NUM= org_division.survey_num) left join org_department on (org_surveylog.department_code = org_department.department_code and org_surveylog.SURVEY_NUM = org_department.survey_num) group by org_surveylog.division_code,org_surveylog.department_code but below is ok select org_surveylog.division_code as divisionCode,org_surveylog.department_code as departmentCode , max(org_surveylog.actiondate) from org_surveylog left join org_division on (org_surveylog.division_code= org_division.division_code and org_surveylog.SURVEY_NUM= org_division.survey_num) left join org_department on (org_surveylog.department_code = org_department.department_code and org_surveylog.SURVEY_NUM = org_department.survey_num) group by org_surveylog.division_code,org_surveylog.department_code how to use group by with left join when i need to show value of org_division.name , org_department.name ?

    Read the article

  • SQL - Rank() on a table

    - by Abhi
    create table v (mydate,value) as select to_date('20/03/2010 00','dd/mm/yyyy HH24'),98 from dual union all select to_date('20/03/2010 01','dd/mm/yyyy HH24'),124 from dual union all select to_date('20/03/2010 02','dd/mm/yyyy HH24'),140 from dual union all select to_date('20/03/2010 03','dd/mm/yyyy HH24'),138 from dual union all select to_date('20/03/2010 04','dd/mm/yyyy HH24'),416 from dual union all select to_date('20/03/2010 05','dd/mm/yyyy HH24'),196 from dual union all select to_date('20/03/2010 06','dd/mm/yyyy HH24'),246 from dual union all select to_date('20/03/2010 07','dd/mm/yyyy HH24'),176 from dual union all select to_date('20/03/2010 08','dd/mm/yyyy HH24'),124 from dual union all select to_date('20/03/2010 09','dd/mm/yyyy HH24'),128 from dual union all select to_date('20/03/2010 10','dd/mm/yyyy HH24'),32010 from dual union all select to_date('20/03/2010 11','dd/mm/yyyy HH24'),384 from dual union all select to_date('20/03/2010 12','dd/mm/yyyy HH24'),368 from dual union all select to_date('20/03/2010 13','dd/mm/yyyy HH24'),392 from dual union all select to_date('20/03/2010 14','dd/mm/yyyy HH24'),374 from dual union all select to_date('20/03/2010 15','dd/mm/yyyy HH24'),350 from dual union all select to_date('20/03/2010 16','dd/mm/yyyy HH24'),248 from dual union all select to_date('20/03/2010 17','dd/mm/yyyy HH24'),396 from dual union all select to_date('20/03/2010 18','dd/mm/yyyy HH24'),388 from dual union all select to_date('20/03/2010 19','dd/mm/yyyy HH24'),360 from dual union all select to_date('20/03/2010 20','dd/mm/yyyy HH24'),194 from dual union all select to_date('20/03/2010 21','dd/mm/yyyy HH24'),234 from dual union all select to_date('20/03/2010 22','dd/mm/yyyy HH24'),328 from dual union all select to_date('20/03/2010 23','dd/mm/yyyy HH24'),216 from dual From this table, how to rank() over 'value', partitioning by each hour of the day? and select only the 1st ranked result?

    Read the article

  • How to move 100mb hidden system reserved partition on Windows Server 2008 R2 to other drive?

    - by Artyom Krivokrisenko
    Hello! I have a server with two 1.5TB hard drives. I was going to install a Windows Server 2008 R2 and create software RAID1 using Windows Disk Management Utility. I instaleld Windows, open this console and that is what I see: http://i.imgur.com/KoC9a.png Setup program created a System Reserved Partition at my second HDD. I don't understand now, how can I create RAID1, because space, which supposed to be used for copy of disk C, now is used for this hidden partition. So is there any way now to create correct RAID1? May it is possible to move this partition to the Disk 0, where I have plenty of free space? Unfortunately I can't reinstall Windows and apply other options at the disk management step of the installation, because installation image is not longer connected to the server and I have no physical access to server, only remote desktop.

    Read the article

  • SQL Server CONTAINS with digits gives no results

    - by dale
    Hi, I have a database table which is full-text indexed and i use the CONTAINS-function to perform a search-query on it. When I do: SELECT * FROM Plants WHERE CONTAINS(Plants.Description, '"Plant*" AND "one*"'); I get back all correct results matching a description with the words "Plant" and "one". Some plant are named like "Plant 1", "Plant 2" etc. and this is the problem. When i do this, i get no results: SELECT * FROM Plants WHERE CONTAINS(Plants.Description, '"Plant*" AND "1*"'); Anyone know why?

    Read the article

  • Windows Server Backup 2012 error - "The version does not support this version of the file format."

    - by Cylindric
    I'm trying out Windows Server 2012, specifically Windows Server Backup, as it would be a very useful way to see us through until we can upgrade our 'real' backup system. I'm backing up to a network share, and a Server 2008 WSB works fine. On the 2012 server however, I get an error: Backup of volume \?\Volume{298d1a7d-f80f-11e1-93e8-806e6f6e6963}\ has failed. The version does not support this version of the file format. It's a VHDX written by WSB, so I'm not sure what version it's complaining about. I can see a whole bunch of files in the destination, so I don't think it's a simple authentication issue, but I only get about 8Mb of VHDX written.

    Read the article

  • Other solution instead of Cursoring

    - by dewacorp.alliances
    Hi there I have the following pivoting table that I manage to do and here's the result and I want to put a bit further. **NTRITCode; NTRIId; Parameter; Usage; Rate** CURRENT; 4; Peak; 100; 0.1 CURRENT; 4; NonPeak; 200; 0.2 PROPOSED; 6; Peak; 100; 0.2 PROPOSED; 6; NonPeak; 200; 0.3 PROPOSED; 8; Peak; 200; 0.3 PROPOSED; 8; NonPeak; 200; 0.5 As you can see there is 2 sets of proposed (ID=6 and 8). I want somehow display like this below so each set has a pair of CURRENT as well as the PROPOSED one as follow: **Sequence; NTRITCode; NTRIId; Parameter; Usage; Rate** 1; CURRENT; 4; Peak; 100; 0.1 1; CURRENT; 4; NonPeak; 200; 0.2 1; PROPOSED; 6; Peak; 100; 0.2 1; PROPOSED; 6; NonPeak; 200; 0.3 2; CURRENT; 4; Peak; 100; 0.1 2; CURRENT; 4; NonPeak; 200; 0.2 2; PROPOSED; 8; Peak; 200; 0.3 2; PROPOSED; 8; NonPeak; 200; 0.5 Again all I can think off is using combination of CURSOR and UNION but is there any TSQL that can do this? Thanks

    Read the article

  • Linq-to-sql Compiled Query is caching result from disposed DataContext

    - by Vladimir Kojic
    Compiled query: public static Func<OperationalDataContext, short, Machine> QueryMachineById = CompiledQuery.Compile((OperationalDataContext db, short machineID) => db.Machines.Where(m => m.MachineID == machineID).SingleOrDefault()); It looks like compiled query is caching Machine object and returning the same object even if query is called from new DataContext (I’m disposing DataContext in the service but I’m getting Machine from previous DataContext). I use POCOs and XML mapping. Getting cached object from the same datacontext is ok, but when I call query with new DataContext I don’t want to get object from old datacontext. Is there something that I don’t do right ? Thanks, Vladimir

    Read the article

  • SQL 2005 indexed queries slower than unindexed queries

    - by uos??
    Adding a seemingly perfectly index is having an unexpectedly adverse affect on a query performance... -- [Data] has a predictable structure and a simple clustered index of the primary key: ALTER TABLE [dbo].[Data] ADD PRIMARY KEY CLUSTERED ( [ID] ) -- My query, joins on itself looking for a certain kind of "overlapping" records SELECT DISTINCT [Data].ID AS [ID] FROM dbo.[Data] AS [Data] JOIN dbo.[Data] AS [Compared] ON [Data].[A] = [Compared].[A] AND [Data].[B] = [Compared].[B] AND [Data].[C] = [Compared].[C] AND ([Data].[D] = [Compared].[D] OR [Data].[E] = [Compared].[E]) AND [Data].[F] <> [Compared].[F] WHERE 1=1 AND [Data].[A] = @A AND @CS <= [Data].[C] AND [Data].[C] < @CE -- Between a range [Data] has about a quarter-million records so far, 10% to 50% of the data satisfies the where clause depending on @A, @CS, and @CE. As is, the query takes 1 second to return about 300 rows when querying 10%, and 30 seconds to return 3000 rows when querying 50% of the data. Curiously, the estimated/actual execution plan indicates two parallel Clustered Index Scans, but the clustered index is only of the ID, which isn't part of the conditions of the query, only the output. ?? If I add this hand-crafted [IDX_A_B_C_D_E_F] index which I fully expected to improve performance, the query slows down by a factor of 8 (8 seconds for 10% & 4 minutes for 50%). The estimated/actual execution plans show an Index Seek, which seems like the right thing to be doing, but why so slow?? CREATE UNIQUE INDEX [IDX_A_B_C_D_E_F] ON [dbo].[Data] ([A], [B], [C], [D], [E], [F]) INCLUDE ([ID], [X], [Y], [Z]); The Data Engine Tuning wizard suggests a similar index with no noticeable difference in performance from this one. Moving AND [Data].[F] <> [Compared].[F] from the join condition to the where clause makes no difference in performance. I need these and other indexes for other queries. I'm sure I could hint that the query should refer to the Clustered Index, since that's currently winning - but we all know it is not as optimized as it could be, and without a proper index, I can expect the performance will get much worse with additional data. What gives?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 484 485 486 487 488 489 490 491 492 493 494 495  | Next Page >