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  • mysql statement with nested SELECT - how to improve performance

    - by ernie
    This statement appears inefficient because only one one out of 10 records are selected and only 1 of 100 entries contain comments. What can I do to improve it ? $query = "SELECT A,B,C, (SELECT COUNT(*) FROM comments WHERE comments.nid = header_file.nid) as my_comment_count FROM header_file Where A = 'admin' " edit: I want header records even if no comments are found.

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  • Msdtc Transaction

    - by Shimjith
    I am using Linked server For Tansaction example Alter Proc [dbo].[usp_Select_TransferingDatasFromServerCheckingforExample] @RserverName varchar(100), ----- Server Name @RUserid Varchar(100), ----- server user id @RPass Varchar(100), ----- Server Password @DbName varchar(100) ----- Server database As Set nocount on Set Xact_abort on Declare @user varchar(100) Declare @userID varchar(100) Declare @Db Varchar(100) Declare @Lserver varchar(100) Select @Lserver = @@servername Select @userID = suser_name() select @User=user Exec('if exists(Select 1 From [Master].[' + @user + '].[sysservers] where srvname = ''' + @RserverName + ''') begin Exec sp_droplinkedsrvlogin ''' + @RserverName + ''',''' + @userID + ''' exec sp_dropserver ''' + @RserverName + ''' end ') set @RserverName='['+@RserverName+']' BEGIN TRY BEGIN TRANSACTION declare @ColumnList varchar(max) set @ColumnList = null select @ColumnList = case when @ColumnList is not null then @ColumnList + ',' + quotename(name) else quotename(name) end from syscolumns where id = object_id('bditm') order by colid set identity_insert Bditm on exec ('Insert Into Bditm ('+ @ColumnList +') Select * From '+ @RserverName + '.'+ @DbName + '.'+ @user + '.Bditm') set identity_insert Bditm off Commit Select 1 End try Begin catch if (@@ERROR < 0) Begin if @@trancount 0 Begin Rollback transaction Select 0 END End End Catch set @RserverName=replace(replace(@RserverName,'[',''),']','') Exec sp_droplinkedsrvlogin @RserverName,@userID Exec sp_dropserver @RserverName this is the Error Occuerd The Microsoft Distributed Transaction Coordinator (MS DTC) has cancelled the distributed transaction.

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  • Running pl/sql in Korn Shell(AIX)

    - by learner135
    I have a file to execute in Ksh written by someone. It has a set of commands to execute in sqlplus. It starts with, sqlplus -s $UP <<- END followed by a set of ddl commands such as create,drop,etc., When I execute the file in the shell, I get the error in the starting line quoted above. I understand "-s" starts the sqlplus in silent mode and $UP is the connection string with username/password. But I couldn't make heads or tails of "<<- END" part(Many sites from google says input redirection is "<<" not "<<-"). So I presumed the error must be in that part and removed it from the file. Now it reads, sqlplus -s $UP But once I execute the file, It waits for input from the shell, instead of reading the rest of the lines from the file. How would I make sqlplus to execute the ddl commands in the rest of the file?. Thanks in advance.

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  • How to move from untyped DataSets to POCO\LINQ2SQL in legacy application

    - by artvolk
    Good day! I've a legacy application where data access layer consists of classes where queries are done using SqlConnection/SqlCommand and results are passed to upper layers wrapped in untyped DataSets/DataTable. Now I'm working on integrating this application into newer one where written in ASP.NET MVC 2 where LINQ2SQL is used for data access. I don't want to rewrite fancy logic of generating complex queries that are passed to SqlConnection/SqlCommand in LINQ2SQL (and don't have permission to do this), but I'd like to have result of these queries as strong-typed objects collection instead of untyped DataSets/DataTable. The basic idea is to wrap old data access code in a nice-looking from ASP.NET MVC "Model". What is the fast\easy way of doing this?

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  • Oracle Database Enforce CHECK on multiple tables

    - by GigaPr
    I am trying to enforce a CHECK Constraint in a ORACLE Database on multiple tables CREATE TABLE RollingStocks ( Id NUMBER, Name Varchar2(80) NOT NULL, RollingStockCategoryId NUMBER NOT NULL, CONSTRAINT Pk_RollingStocks Primary Key (Id), CONSTRAINT Check_RollingStocks_CategoryId CHECK ((RollingStockCategoryId IN (SELECT Id FROM FreightWagonTypes)) OR (RollingStockCategoryId IN (SELECT Id FROM LocomotiveClasses))) ); ...but i get the following error: *Cause: Subquery is not allowed here in the statement. *Action: Remove the subquery from the statement. Can you help me understanding what is the problem or how to achieve the same result?

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  • deleting records from multiple tables at a time with a single query in sqlserver2005

    - by sudhavamsikiran
    Hi I wanna delete records from child tables as well as parent table with in a single query. please find the query given below. here response header is the primary table and responseid is the primary key. DELETE FROM responseheader FROM responseheader INNER JOIN responsepromotion ON responseheader.responseid = responsepromotion.ResponseID INNER JOIN responseext ON responsepromotion.ResponseID=responseext.ResponseID WHERE responseheader.responseid In ('67D8B9E8-BAD2-42E6-BAEA-000025D56253') but its throwing error . can any one help me to find out the correct query

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  • How to switch from MSSQL to MySQL for using with Excel pivot

    - by Sim
    Hi all, I have a table that contains sales transaction (~20 mil rows). Previously I used MSSQL and export it to an Excel pivot. Data refresh took 10-15 minutes but still do-able. However, after I migrated to MySQL (using XamppLite & ODBC), it took forever to refresh the data in the Excel pivot. Maybe I didn't optimize the MySQL good enough ? Anyone can share some thoughts 'bout this ? Thanks

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  • How do these user/userParam references relate to the Customer and Account lookups?

    - by plath
    In the following code example how do the user/userParam references relate to the Customer and Account lookups and what is the relationship between Customer and Account? // PersistenceManager pm = ...; Transaction tx = pm.currentTransaction(); User user = userService.currentUser(); List<Account> accounts = new ArrayList<Account>(); try { tx.begin(); Query query = pm.newQuery("select from Customer " + "where user == userParam " + "parameters User userParam"); List<Customer> customers = (List<Customer>) query.execute(user); query = pm.newQuery("select from Account " + "where parent-pk == keyParam " + "parameters Key keyParam"); for (Customer customer : customers) { accounts.addAll((List<Account>) query.execute(customer.key)); } } finally { if (tx.isActive()) { tx.rollback(); } }

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  • 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.

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  • Update table variable with function

    - by Joris
    I got a table variable @RQ, I want it updated using a table-valued function. Now, I think I do the update wrong, because my function works... The function: ALTER FUNCTION [dbo].[usf_GetRecursiveFoobar] ( @para int, @para datetime, @para varchar(30) ) RETURNS @ReQ TABLE ( Onekey int, Studnr nvarchar(10), Stud int, Description nvarchar(32), ECTSGot decimal(5,2), SBUGot decimal(5,0), ECTSmax decimal(5,2), SBUmax decimal(5,0), IsFree bit, IsGot int, DateGot nvarchar(10), lvl int, path varchar(max) ) AS BEGIN; WITH RQ AS ( --RECURSIVE QUERY ) INSERT @ReQ SELECT RQ.Onekey, RQ.Studnr, RQ.Stud, RQ.Description, RQ.ECTSGot, RQ.SBUGot, RQ.ECTSmax, RQ.SBUmax, RQ.IsFree, RQ.IsGot, RQ.DatumGot, RQ.lvl, RQ.path FROM RQ RETURN END Now, when I run a simple query: DECLARE @ReQ TABLE ( OnderwijsEenheid_key int, StudentnummerHSA nvarchar(10), Student_key int, Omschrijving nvarchar(32), ECTSbehaald decimal(5,2), SBUbehaald decimal(5,0), ECTSmax decimal(5,2), SBUmax decimal(5,0), IsVrijstelling bit, IsBehaald int, DatumBehaald nvarchar(10), lvl int, path varchar(max) ) INSERT INTO @ReQ SELECT * FROM usf_GetRecursiveFoobar(@para1, @para2, @para3) I got error: Msg 8152, Level 16, State 13, Line 20 String or binary data would be truncated. The statement has been terminated. Why? What to do about it?

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  • How to avoid overlapping date ranges when using a grouping clause?

    - by k rey
    I have a situation where I need to find time spans between value changes. I tried a simple group by clause but it eliminates overlapping changes. Consider the following example: create table #items ( code varchar(4) , class varchar(4) , txdate datetime ) insert into #items (code, class, txdate) values ('A', 'C', '2010-01-01'); insert into #items (code, class, txdate) values ('A', 'C', '2010-01-02'); insert into #items (code, class, txdate) values ('A', 'C', '2010-01-03'); insert into #items (code, class, txdate) values ('A', 'D', '2010-01-04'); insert into #items (code, class, txdate) values ('A', 'D', '2010-01-05'); insert into #items (code, class, txdate) values ('A', 'C', '2010-01-06'); insert into #items (code, class, txdate) values ('A', 'C', '2010-01-07'); insert into #items (code, class, txdate) values ('A', 'D', '2010-01-08'); insert into #items (code, class, txdate) values ('A', 'D', '2010-01-09'); select code , class , min(txdate) mindate , max(txdate) maxdate from #items group by code, class This returns the following results (notice the overlapping date ranges): |code|class|mindate |maxdate | ---------------------------------- |A |C |2010-01-01|2010-01-07| |A |D |2010-01-04|2010-01-09| I would like to have the query return the following: |code|class|mindate |maxdate | ---------------------------------- |A |C |2010-01-01|2010-01-03| |A |D |2010-01-04|2010-01-05| |A |C |2010-01-06|2010-01-07| |A |D |2010-01-08|2010-01-09| Any ideas and suggestions?

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  • sqlite3 timestamp column

    - by Flavius
    Hi I feel stupid, but I can't get a TIMESTAMP column to be shown in human understandable way in a SELECT. I could do that in MySQL, not in sqlite3. Could someone show me an example please? Thanks

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  • Group functions of outer query inside inner query

    - by superdario
    Hello, I'm using Oracle. I'm trying to compose something like this: SELECT trans_type, (SELECT parameter_value FROM transaction_details WHERE id = MAX(t.trans_id)) FROM (SELECT trans_id, trans_type FROM transactions) t GROUP BY trans_type So, I am trying to use a result of grouping inside an inner query. But I am getting the error that I cannot use a group function inside the inner query: ORA-00934: group function is not allowed here Can you offer an alternative other than resorting to another outer query?

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  • Using OUTPUT/INTO within instead of insert trigger invalidates 'inserted' table

    - by Dan
    I have a problem using a table with an instead of insert trigger. The table I created contains an identity column. I need to use an instead of insert trigger on this table. I also need to see the value of the newly inserted identity from within my trigger which requires the use of OUTPUT/INTO within the trigger. The problem is then that clients that perform INSERTs cannot see the inserted values. For example, I create a simple table: CREATE TABLE [MyTable]( [MyID] [int] IDENTITY(1,1) NOT NULL, [MyBit] [bit] NOT NULL, CONSTRAINT [PK_MyTable_MyID] PRIMARY KEY NONCLUSTERED ( [MyID] ASC )) Next I create a simple instead of trigger: create trigger [trMyTableInsert] on [MyTable] instead of insert as BEGIN DECLARE @InsertedRows table( MyID int, MyBit bit); INSERT INTO [MyTable] ([MyBit]) OUTPUT inserted.MyID, inserted.MyBit INTO @InsertedRows SELECT inserted.MyBit FROM inserted; -- LOGIC NOT SHOWN HERE THAT USES @InsertedRows END; Lastly, I attempt to perform an insert and retrieve the inserted values: DECLARE @tbl TABLE (myID INT) insert into MyTable (MyBit) OUTPUT inserted.MyID INTO @tbl VALUES (1) SELECT * from @tbl The issue is all I ever get back is zero. I can see the row was correctly inserted into the table. I also know that if I remove the OUTPUT/INTO from within the trigger this problem goes away. Any thoughts as to what I'm doing wrong? Or is how I want to do things not feasible? Thanks.

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  • How do I track down sporadic ASP.NET performance problems in a production environment?

    - by Steve Wortham
    I've had sporadic performance problems with my website for awhile now. 90% of the time the site is very fast. But occasionally it is just really, really slow. I mean like 5-10 seconds load time kind of slow. I thought I had narrowed it down to the server I was on so I migrated everything to a new dedicated server from a completely different web hosting company. But the problems continue. I guess what I'm looking for is a good tool that'll help me track down the problem, because it's clearly not the hardware. I'd like to be able to log certain events in my ASP.NET code and have that same logger also track server performance/resources at the time. If I can then look back at the logs then I can see what exactly my website was doing at the time of extreme slowness. Is there a .NET logging system that'll allow me to make calls into it with code while simultaneously tracking performance? What would you recommend?

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  • union on the same table

    - by StupidDeveloper
    I have a table: ID | Id1 | Id2 1 | 100 | 12 2 | 196 | 140 3 | 196 | 141 4 | 150 | 140 5 | 150 | 199 I want to write a query that will give me a table containing records with the same ID2 and with id1 equal to 196 or 150. I thought about union: select * from table where itemId = 196 union select * from table where itemId = 150 but that doesn't cover the ID2 requirement. How should I do that?

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  • Updating multiple tables with LinqToSql in one unit of work

    - by zsharp
    Table 1: int ID-a(pk) Table 2: int ID-a(pk), int ID-b(pk) Table 3: int ID-b(pk), string C I have the data to insert into Table 1. But I do not have the ID-a, which is autogenerated. I have many string C to insert in Table 3. I am trying to insert row into Table 1, get the ID-a to insert in Table 2 along with the ID-b that is auto-Generated in Table 3 when I submit each string C, all in one submission to db. Right now I am calling dc.SubmitChanges twice in same call. Is it efficient to have to submit changes twice on same DataContext or can this be combined further?

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  • Foreign Key Relationships and "belongs to many"

    - by jan
    I have the following model: S belongs to T T has many S A,B,C,D,E (etc) have 1 T each, so the T should belong to each of A,B,C,D,E (etc) At first I set up my foreign keys so that in A, fk_a_t would be the foreign key on A.t to T(id), in B it'd be fk_b_t, etc. Everything looks fine in my UML (using MySQLWorkBench), but generating the yii models results in it thinking that T has many A,B,C,D (etc) which to me is the reverse. It sounds to me like either I need to have A_T, B_T, C_T (etc) tables, but this would be a pain as there are a lot of tables that have this relationship. I've also googled that the better way to do this would be some sort of behavior, such that A,B,C,D (etc) can behave as a T, but I'm not clear on exactly how to do this (I will continue to google more on this) What do you think is the better solution? UML: Here's the DDL (auto generated). Just pretend that there is more than 3 tables referencing T. -- ----------------------------------------------------- -- Table `mydb`.`T` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `mydb`.`T` ( `id` INT NOT NULL AUTO_INCREMENT , PRIMARY KEY (`id`) ) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`S` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `mydb`.`S` ( `id` INT NOT NULL AUTO_INCREMENT , `thing` VARCHAR(45) NULL , `t` INT NOT NULL , PRIMARY KEY (`id`) , INDEX `fk_S_T` (`id` ASC) , CONSTRAINT `fk_S_T` FOREIGN KEY (`id` ) REFERENCES `mydb`.`T` (`id` ) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`A` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `mydb`.`A` ( `id` INT NOT NULL AUTO_INCREMENT , `T` INT NOT NULL , `stuff` VARCHAR(45) NULL , `bar` VARCHAR(45) NULL , `foo` VARCHAR(45) NULL , PRIMARY KEY (`id`) , INDEX `fk_A_T` (`T` ASC) , CONSTRAINT `fk_A_T` FOREIGN KEY (`T` ) REFERENCES `mydb`.`T` (`id` ) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`B` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `mydb`.`B` ( `id` INT NOT NULL AUTO_INCREMENT , `T` INT NOT NULL , `stuff2` VARCHAR(45) NULL , `foobar` VARCHAR(45) NULL , `other` VARCHAR(45) NULL , PRIMARY KEY (`id`) , INDEX `fk_A_T` (`T` ASC) , CONSTRAINT `fk_A_T` FOREIGN KEY (`T` ) REFERENCES `mydb`.`T` (`id` ) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `mydb`.`C` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `mydb`.`C` ( `id` INT NOT NULL AUTO_INCREMENT , `T` INT NOT NULL , `stuff3` VARCHAR(45) NULL , `foobar2` VARCHAR(45) NULL , `other4` VARCHAR(45) NULL , PRIMARY KEY (`id`) , INDEX `fk_A_T` (`T` ASC) , CONSTRAINT `fk_A_T` FOREIGN KEY (`T` ) REFERENCES `mydb`.`T` (`id` ) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB;

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  • Ruby on rails active-record generated SQL on Postgres

    - by jpartogi
    Dear all, Why does Ruby on rails generated more queries in the background on Postgres than MySQL? I haven't tried deploying Rails on production with Postgres yet, but I am just afraid this generated queries would affect the performance. Do you find Rails with Postgres is slower than MySQL, knowing that it produce more query on the background? Or it is relatively the same?

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  • Why does this query only select a single row?

    - by Joe
    SELECT * FROM tbl_houses WHERE (SELECT HousesList FROM tbl_lists WHERE tbl_lists.ID = '123') LIKE CONCAT('% ', tbl_houses.ID, '#') It only selects the row from tbl_houses of the last occuring tbl_houses.ID inside tbl_lists.HousesList I need it to select all the rows where any ID from tbl_houses exists within tbl_lists.HousesList

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  • SSIS 2005 - How to Import a Fixed Width Flat File?

    - by Greg
    I have a flat file that looks something like this: junk I don't care about \n \n columns names\n val1 val2 val3\n val1 val2 val3\n columns names \n val1 val2 val3\n I only care the lines with values. These value lines are all fixed width format and have the same line length. The other junk lines and column names can have any line width. When I try the flat file fixed width option or the ragged right option the preview looks all wrong. Any ideas what the easiest way to get this into SSIS is?

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  • Copy mdf file and use it in run time

    - by Anibas
    After I copy mdf file (and his log file) I tries to Insert data. I receive the following message: "An attempt to attach an auto-named database for file [fileName].mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share. When I copied the file manual everything worked normally. Is it correct the order File.Copy leaves the file engaged?

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  • joins- how to pass the parameter in stored procedure to execute a join query

    - by Ranjana
    i have used joins to get datas from two tables under comman name. as SELECT userValidity.UserName, userValidity.ValidFrom,userValidity.ValidUpTo,userValidity.TotalPoints, persons.SenderID FROM userValidity INNER JOIN persons ON userValidity.Username=tbl_persons.Username but i need to execute this query with oly the username which i pass as parameter in stored procedure.. how to pass the username in stored procedure in this joins. alter procedure GetNameIDUserInformation ( @user varchar(max) ) as begin SELECT userValidity.UserName, userValidity.ValidFrom,userValidity.ValidUpTo,userValidity.TotalPoints, persons.SenderID FROM userValidity INNER JOIN persons ON userValidity.Username=tbl_persons.Username end in this SP, where i have to pass the user parameter to get the single row of my user record

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