Dynamic Cursor Versus Forward Only Cursor Gives Poor Performance

Jul 20, 2005

Hello,

I have a test database with table A containing 10,000 rows and a table
B containing 100,000 rows. Rows in B are "children" of rows in A -
each row in A has 10 related rows in B (ie. B has a foreign key to A).

Using ODBC I am executing the following loop 10,000 times, expressed
below in pseudo-code:

"select * from A order by a_pk option (fast 1)"
"fetch from A result set"
"select * from B where where fk_to_a = 'xxx' order by b_pk option
(fast 1)"
"fetch from B result set" repeated 10 times

In the above psueod-code 'xxx' is the primary key of the current A
row. NOTE: it is not a mistake that we are repeatedly doing the A
query and retrieving only the first row.

When the queries use fast-forward-only cursors this takes about 2.5
minutes. When the queries use dynamic cursors this takes about 1 hour.

Does anyone know why the dynamic cursor is killing performance?
Because of the SQL Server ODBC driver it is not possible to have
nested/multiple fast-forward-only cursors, hence I need to explore
other alternatives.

I can only assume that a different query plan is getting constructed
for the dynamic cursor case versus the fast forward only cursor, but I
have no way of finding out what that query plan is.

All help appreciated.

Kevin

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Cursor Versus While Loop

Oct 29, 2007

I have always been told that Cursors create a lot of overhead and consume a lot of system resources. Is it faster to store the data in a temp table and loop through it by using Select Top 1 and Delete statements or by using a static, Forward-Only Cursor? Both ways store the data in TempDB, but doesn't the While Loop statement generate more IO's than the Cursor? In theory, I am thinking that the Cursor is better. Any info will be appreciated.

Thanks!!

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Cursor Looping Versus Set-based Queries

Mar 28, 2006

I know this question has been asked. And the usual answer is don't usecursors or any other looping method. Instead, try to find a solutionthat uses set-based queries.But this brings up several questions / senarios:* I created several stored procedures that take parameters and insertsthe data into the appropriate tables. This was done for easy access/usefrom client side apps (i.e. web-based).Proper development tactics says to try and do "code reuse". So, if Ialready have stored procs that do my logic, should I be writing asecond way of handling the data? If I ever need to change the way thedata is handled, I now have to make the same change in two (or more)places.* Different data from the same row needs to be inserted into multipletables. "Common sense" (maybe "gut instinct" is better) says to handleeach row as a "unit". Seems weird to process the entire set for onetable, then to process the entire set AGAIN for another table, and thenYET AGAIN for a third table, and so on.* Exception handling. Set based processing means that if one row failsthe entire set fails. Looping through allows you to fail a row butallow everything else to be processed properly. It also allows you togather statistics. (How many failed, how many worked, how many wereskipped, etc.)?? Good idea ?? The alternative is to create a temporary table (sandboxor workspace type thing), copy the data to there along with "status" or"valdation" columns, run through the set many times over looking forany rows that may fail, marking them as such, and then at the end onlydealing with those rows which "passed" the testing. Of course, in orderfor this to work you must know (and duplicate) all constraints so youknow what to look for in your testing.

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Aug 12, 2015

In MSDN file I read about static cursor

STATIC
Defines a cursor that makes a temporary copy of the data to be used by the cursor. All requests to the cursor are answered from this temporary table in
tempdb; therefore, modifications made to base tables are not reflected in the data returned by fetches made to this cursor, and this cursor does not allow modifications

It say's that modifications is not allowed in the static cursor. I have a  questions regarding that

Static Cursor
declare ll cursor global static
            for select  name, salary from ag
  open ll
             fetch from ll
 
              while @@FETCH_STATUS=0
               fetch from ll
                update ag set salary=200 where 1=1
 
   close ll
deallocate ll

In "AG" table, "SALARY" was 100 for all the entries. When I run the Cursor, it showed the salary value as "100" correctly.After the cursor was closed, I run the query select * from AG.But the result had updated to salary 200 as given in the cursor. file says  modifications is not allowed in the static cursor.But I am able to update the data using static cursor.

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Could Not Complete Cursor Operation Because The Set Options Have Changed Since The Cursor Was Declared.

Sep 20, 2007

I'm trying to implement a sp_MSforeachsp howvever when I call sp_MSforeach_worker
I get the following error can you please explain this problem to me so I can over come the issue.


Msg 16958, Level 16, State 3, Procedure sp_MSforeach_worker, Line 31

Could not complete cursor operation because the set options have changed since the cursor was declared.

Msg 16958, Level 16, State 3, Procedure sp_MSforeach_worker, Line 32

Could not complete cursor operation because the set options have changed since the cursor was declared.

Msg 16917, Level 16, State 1, Procedure sp_MSforeach_worker, Line 153

Cursor is not open.

here is the stored procedure:


Alter PROCEDURE [dbo].[sp_MSforeachsp]

@command1 nvarchar(2000)

, @replacechar nchar(1) = N'?'

, @command2 nvarchar(2000) = null

, @command3 nvarchar(2000) = null

, @whereand nvarchar(2000) = null

, @precommand nvarchar(2000) = null

, @postcommand nvarchar(2000) = null

AS

/* This procedure belongs in the "master" database so it is acessible to all databases */

/* This proc returns one or more rows for each stored procedure */

/* @precommand and @postcommand may be used to force a single result set via a temp table. */

declare @retval int

if (@precommand is not null) EXECUTE(@precommand)

/* Create the select */

EXECUTE(N'declare hCForEachTable cursor global for

SELECT QUOTENAME(SPECIFIC_SCHEMA)+''.''+QUOTENAME(ROUTINE_NAME)

FROM INFORMATION_SCHEMA.ROUTINES

WHERE ROUTINE_TYPE = ''PROCEDURE''

AND OBJECTPROPERTY(OBJECT_ID(QUOTENAME(SPECIFIC_SCHEMA)+''.''+QUOTENAME(ROUTINE_NAME)), ''IsMSShipped'') = 0 '

+ @whereand)

select @retval = @@error

if (@retval = 0)

EXECUTE @retval = [dbo].sp_MSforeach_worker @command1, @replacechar, @command2, @command3, 0

if (@retval = 0 and @postcommand is not null)

EXECUTE(@postcommand)

RETURN @retval



GO


example useage:


EXEC sp_MSforeachsp @command1="PRINT '?' GRANT EXECUTE ON ? TO [superuser]"

GO

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Dynamic SQL In Cursor

Jun 10, 2004

I need to pass a list of values into a cursor as such...


DECLARE
@group_SQL varchar(255)

SET @group_SQL = 'SELECT group_id FROM groups where group_id in (' + @group_id + ')'

DECLARE groupContact_import_cursor CURSOR
FOR EXEC(@group_SQL)
OPEN groupContact_import_cursor
FETCH NEXT FROM groupContact_import_cursor INTO @group_id
WHILE (@@FETCH_STATUS = 0)
BEGIN
insert into groupContacts (group_id, contact_id) values (@group_id, @new_cid)
FETCH NEXT FROM groupContact_import_cursor INTO @group_id
END
CLOSE groupContact_import_cursor
DEALLOCATE groupContact_import_cursor

But MS SQL doesn't seem to like the FOR EXEC(@group_SQL). Can someone shed some light?

TIA

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Mar 17, 2004

I am trying to use a dynamic cursor in a stored procedure:
The code looks like this :


/************************************************** ***
set @sFormula = 'Monthlyformula'
set @sStartDate = '02/01/2004'
set @sEndDate = '02/01/2004'


exec('DECLARE APPGRIDROWS_METRICS CURSOR FOR select populateid From appgridrows where histdisplaygrid = 3 And '+ @sFormula +' Is Null and exists (SELECT 1 From PAYROLL_DATA_PERIOD as h Where h.id=1 and h.populateid=appgridrows.populateid and h.StartDate between '+ @sStartDate +' and '+ @sEndDate +')' )
/************************************************** ***

And this is what it is interpreting

select populateid From appgridrows where histdisplaygrid = 3 And Monthlyformula Is Null and exists (SELECT 1 From PAYROLL_DATA_PERIOD as h Where h.id=1 and h.populateid=appgridrows.populateid and h.StartDate between 02/01/2004 and 02/01/2004)

My problem is Is there anyway that I can put the quotes before those dates('02/01/2004') so that my cursor has some records returned

Thanks in advance

SK

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Sep 23, 2005

Dear folks,

In My Query i am using where in condition .It return multiple record .I want store it in to cursor and perform the operation.

Declare @sql varchar(5000);
set @sql='select * from Role where Role_id in('+ @role_ids +')';
Exec @sql;

I want take this record set in to cursor .How to do it.
please help me.

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May 26, 2007

Hi All€¦

I need to bind a DataGrid to server dynamic cursor.

Please help!

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Jul 23, 2002

Hello..

Can you declare a cursor with dynamic SQL?

I have a situation where the SQL for my cursor MUST be assembled in a buffer, but I cannot get the cursor declaration to accept my buffer as the SQL statement.

these attempts did not work:

DECLARE crsCursor CURSOR FOR @vchrSQL
DECLARE crsCursor CURSOR FOR (@vchrSQL)

Does anybody know if you definitely can or definitely cannot use dynamic SQL with cursors?

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May 14, 2008

Hi all

I am trying to do dynamic Select for Cursor. The dynamic would be like this:
IF CONDITION1 IS TRUE:
SELECT CustomerTenderID, CustomerSiteID, ContractPeriod, SupplierID
FROM dbo.tnd_TenderSiteRateConsumptionView
WHERE CustomerTenderID = @CustomerTenderID
IF CONDITION2 IS TRUE:
SELECT CustomerTenderID, CustomerSiteID, ContractPeriod, SupplierID
FROM dbo.tnd_TenderSiteRateConsumptionView
WHERE CustomerTenderID = @CustomerTenderID AND
CustomerSiteID = @CustomerSiteID

etc etc

Here's the cursor


DECLARE RateList CURSOR FOR
SELECT CustomerTenderID, CustomerSiteID, ContractPeriod, SupplierID
FROM dbo.tnd_TenderSiteRateConsumptionView
WHERE (BASED ON CONDITION)
ORDER BY CustomerTenderID,
CustomerSiteID,
SupplierID,
ContractPeriod

OPEN RateList
FETCH NEXT FROM RateList
INTO@CustomerTenderID, @ReturnedCustomerSiteID, @ReturnedContractPeriod, @ReturnedSupplierID
WHILE @@FETCH_STATUS = 0
BEGIN
SET @rowNum = @rowNum + 1

-- DO SOME FUNKY STUFF


FETCH NEXT
FROM RateList
INTO@CustomerTenderID, @ReturnedCustomerSiteID, @ReturnedContractPeriod, @ReturnedSupplierID

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Jul 20, 2005

Help please,Have a situation when converting from Oracle SP's to SQL SP's. The oldoracle cursor was roughly as followsCURSOR cur_rsStock ISselect*from(select StockRowId, CategoryIdfromSTOCKDISPOSABLEwhereSTOCKDEFID=numDefIdORDER BYSTOCKROWID)whereROWNUM <= numQuantity;The closest I can get in MS SQL is as follows :declare cur_rsStockCURSOR forselect top @numQuantityStockRowId, CategoryIdfromSTOCKDISPOSABLEwhereSTOCKDEFID=numDefIdORDER BYSTOCKROWIDBut, SQL doesn't allow variables next to top. I know I can assign the wholeselect statement to a string and use exec to exec the string to get arecordset but how can I point a cursor to receive its output?i.e.set @strSQl = select top ' + @numQuantity + ' StockRowId, CategoryId.......exec @strSQLbut how do I dodeclare cur_rsStockset cur_rsStock = ( exec @strSQL)Flapper

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Jul 20, 2005

Hi Everybody,I have a probs with dynamic generation.I am writing the probs======================================create proc testasdeclare @query varchar(500)set @query = 'select * from table'----------------------------------------------declare mycur Cursor for Select * from table |open mycur |----------------------------------------------but instate of above block how can I dynamically generate this query?---------------------------------------declare mycur Cursor for exec (@query) |---------------------------------------Or tell me the way.RegardsArijit Chatterjee

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Jun 29, 2000

"Cursor provide row-by-row level processing and it will store the result sets in 'TEMPDB' database".

(Because of this) or (By using Cursor in Triggers or Stored Procedures) the performance will increase or performance will come down?. I am thankful if I get a good reason for this?

Srinivasan

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Jan 10, 2002

Hey,



I have a stored procedure below that loops through a table and updates another table. I used to do this client side in vb but was hoping for better performance when doing everything server side.

Question;



Am I doing something wrng since the query is that slow.?
Why is cursors so bad ?


Thanks



David





ALTER PROCEDURE usp_setinternational

AS

Declare @acnt_no int

declare @cntry_code varchar(10)

declare @counter int

declare @error int

declare MyC cursor

Local

for

SELECT ACNT_NO, COUNTRY_CODE FROM INTNL_ACNT

open MyC

fetch next from MyC into @acnt_no,@cntry_code

select @counter = 1

while @@fetch_status = 0

begin

update xform2 set

address_type='m'

where acnt_no = @acnt_no

update addr set delivery='m',cntry_cde= @cntry_code

where addr_id in (select addr_id from acnt_addr where acnt_no = @acnt_no)

select @counter = @counter +1

fetch next from MyC into @acnt_no,@cntry_code

end

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Apr 23, 2008

hi friends i am using a cursors to fetch data row by row , but the main problem is it takes a very big time span to execute can anybody help me out to replace cursor with some other method or trick so that i can make it perform fast... see my query is like this:

--update cdr set destinationid = null

DECLARE @CDRID BIGINT;

DECLARE @CodeDestID BIGINT;

DECLARE @TempCodeDestID BIGINT;

DECLARE @CtryCode VARCHAR(20);

DECLARE @MATCH INT;

DECLARE @dialed_digits NVARCHAR(50);
DECLARE @FormattedNbr VARCHAR(50);
DECLARE @CountryCode VARCHAR(2);
DECLARE CDR_cursor CURSOR FOR SELECT CDRID, dialed_digits FROM mydata.dbo.CDR WHERE DestinationID IS NULL
OPEN CDR_cursor

FETCH NEXT FROM CDR_cursor INTO @CDRID, @dialed_digits

WHILE @@FETCH_STATUS = 0

BEGIN

SET @FormattedNbr = replace(LTRIM(RTRIM(@dialed_digits)), '"', '');

SET @CountryCode = substring(@FormattedNbr, 0, 3);

SET @CodeDestID = null;

SET @MATCH = 0;

DECLARE Dest_cursor CURSOR FOR SELECT DestinationID, Code FROM mydata.dbo.ctryCode WHERE code Like LTRIM(RTRIM(@CountryCode)) +'%' Order by code Desc

OPEN Dest_cursor

FETCH NEXT FROM Dest_cursor INTO @TempCodeDestID, @CtryCode

WHILE @@FETCH_STATUS = 0

BEGIN

IF @MATCH <> 1

BEGIN

SET @MATCH = PATINDEX(@CtryCode + '%', @FormattedNbr);

IF @MATCH = 1

BEGIN

print @TempCodeDestID

SET @CodeDestID = @TempCodeDestID

END
END

FETCH NEXT FROM Dest_cursor INTO @TempCodeDestID, @CtryCode

END

CLOSE Dest_cursor

DEALLOCATE Dest_cursor

IF @MATCH = 1

BEGIN

--Updating the maximum possible match

UPDATE mydata.dbo.CDR SET DestinationID = @CodeDestID WHERE CDRID = @CDRID

SET @CodeDestID = null;

SET @MATCH = 0;

END
FETCH NEXT FROM CDR_cursor INTO @CDRID, @dialed_digits

END

CLOSE CDR_cursor

DEALLOCATE CDR_cursor


SELECT mydata.dbo.CDR.CDRID, mydata.dbo.CDR.start_date_time, mydata.dbo.CDR.ani, mydata.dbo.CDR.dialed_digits, mydata.dbo.CDR.actual_dur, mydata.dbo.CDR.rounded_dur_secs,mydata.dbo.CDR.cost, mydata.dbo.CtryCode.Destination, mydata.dbo.CtryCode.Code,

mydata.dbo.CtryCode.Cost AS Code_Rate

FROM mydata.dbo.CDR LEFT OUTER JOIN

mydata.dbo.CtryCode ON mydata.dbo.CDR.DestinationID = mydata.dbo.CtryCode.DestinationID


please help me its urgent.....

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Apr 27, 2006

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Oct 6, 2006

Hello everybody!I have a small table "ABC" like this:id_position | value---------------------------1 | 112 | 223 | 33I try to use a dynamic cursor as below.When the statement "order by id_position" in declare part of the cursor_abcis omitted - cursor work as it should.But when the statement "order by id_position" is used, cursor behave asstatic one.What's the matter, does anybody know?Code:declare @id_position as int, @value as intDECLARE cursor_abc CURSORFORselect id_position, value from abcorder by id_positionset nocount onopen cursor_abcFETCH NEXT FROM cursor_abcINTO @id_position, @valueWHILE @@FETCH_STATUS = 0BEGINprint @id_positionprint @valueprint '----------------------------'update abc set value=666 --next reading should give value=666FETCH NEXT FROM cursor_abcINTO @id_position, @valueENDCLOSE cursor_abcDEALLOCATE cursor_abcGORegardsLucas

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Oct 24, 2004

I've looked up Books Online on Dynamic Cursor/ Dynamic SQL Statement.

Using the examples given in Books Online returns compilation errors. See below.

Does anyone know how to use Dynamic Cursor/ Dynamic SQL Statement?

James



-- SQL ---------------

EXEC SQL BEGIN DECLARE SECTION;
char szCommand[] = "SELECT au_fname FROM authors WHERE au_lname = ?";
char szLastName[] = "White";
char szFirstName[30];
EXEC SQL END DECLARE SECTION;

EXEC SQL
DECLARE author_cursor CURSOR FOR select_statement;

EXEC SQL
PREPARE select_statement FROM :szCommand;

EXEC SQL OPEN author_cursor USING :szLastName;
EXEC SQL FETCH author_cursor INTO :szFirstName;



--Error--------------------
Server: Msg 170, Level 15, State 1, Line 23
Line 23: Incorrect syntax near ';'.
Server: Msg 1038, Level 15, State 1, Line 24
Cannot use empty object or column names. Use a single space if necessary.
Server: Msg 1038, Level 15, State 1, Line 25
Cannot use empty object or column names. Use a single space if necessary.
Server: Msg 170, Level 15, State 1, Line 27
Line 27: Incorrect syntax near ';'.
Server: Msg 170, Level 15, State 1, Line 30
Line 30: Incorrect syntax near 'select_statement'.
Server: Msg 170, Level 15, State 1, Line 33
Line 33: Incorrect syntax near 'select_statement'.
Server: Msg 102, Level 15, State 1, Line 35
Incorrect syntax near 'author_cursor'.
Server: Msg 170, Level 15, State 1, Line 36
Line 36: Incorrect syntax near ':'.

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Hi,

I am declaring the cursor based on a query which is generated dynamically. but it is not working



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declare cursor test for @tempsql

open test



This code is not working.



please suggest



Nitin

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CREATE FUNCTION MyTableFunction() 
RETURNS @MyTable TABLE (MYFIELD INTEGER)
AS
BEGIN
  DECLARE @xxx INTEGER
  DECLARE My_Cursor CURSOR DYNAMIC FOR
 
[code]...

I would like the number of rows retruned by MyTableFunction limited to 2, but NOT the inside proc cursor's select !Set Rowcount 0 is forbidden in table function. I cannot use TOP in select * from MyTableFunction instead of setting ROWCOUNT to 2. I'm using SQL Server 2008 or 2012.

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For sample:

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How can I do ???

My code:

Declare @idRelat int, @cmd_FROM nvarchar(1024), @cmd_Det nvarchar(50)
SELECT @idRelat = idRelat, @cmd_Det = cmd_DET
FROM Relatórios WHERE Nome = @p_Relat

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@Aux_Select nvarchar(1024), @Aux_Group nvarchar(1024), @Aux_Order nvarchar(1024)

Select @Tot_Col = 0
Select @Tot_Lin = 0
Select @Campos = 0
Select @Aux_Select = "SELECT " + @cmd_DET + "AS Soma"
Select @Aux_Group = "GROUP BY "
Select @Aux_Order = "ORDER BY "
Declare @a_Local char(1), @a_Linha smallint, @a_Campo nvarchar(50)
Declare cur_Aux insensitive cursor for
SELECT Local, Linha, Campo
From Relatórios_Margens
WHERE (idRelat = @idRelat)
ORDER BY Local, Linha
Open cur_Aux
Fetch cur_Aux into @a_Local, @a_Linha, @a_Campo
While @@FETCH_status = 0 begin
If @a_Local = "C"
Select @Tot_Col = @Tot_Col + 1
Else
Select @Tot_Lin = @Tot_Lin + 1
Select @Campos = @Campos + 1
If @Aux_Group <> "GROUP BY " begin
Select @Aux_Group = @Aux_Group + ", "
If @Aux_Order <> "ORDER BY " begin
Select @Aux_Order = @Aux_Order + ", "
Select @Aux_Select = sSelect + ", " + @a_Campo + " AS Campo" + @Campos
Select @Aux_Group = @Aux_Group + @a_Campo
Select @Aux_Order = @Aux_Order + @a_Campo
Fetch cur_Aux into @a_Local, @a_Linha, @a_Campo
End
Select @Aux_Select = @Aux_Select
-- <<<< MONTA COMANDO SQL
Select @Aux_Select = @Aux_Select + " " + @cmd_FROM + " " + @p_Filtro + " " + @Aux_Group + " " + @Aux_Order
Declare @Cursor_Aux cursor
Set @Cursor_Aux = cursor for @Aux_Select
Open @Cursor_Aux

Not working !!!!

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Hi,
In a stored procedure (SP1) I call another stored procedure (SP2), passing along parameters. In SP2 I dynamically build cursor c1. I can execute SP2 without any problems but when I start SP1 I get the following message:

Msg 16916, Level 16, State 1, Procedure SP2, Line 114
A cursor with the name 'C1' does not exist.

Yes, the cursor is of type GLOBAL. I am sure I miss something here ...
Any help is highly appreciated !

Thanks: Peter

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Declare @query varchar(512)
DECLARE Itera CURSOR --LOCAL STATIC READ_ONLY FORWARD_ONLY
FOR
select --TOP 1000000

[code]....

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The requirement is create a sql script(1 proc or cursor) which will create multiple procedures dynamically.

Table A
Col1 
Col2

A
Alpha

For Example: If table A has 3 rows(distinct) so 3 procedures will be created dynamically.

Result: 
1 PROC_A_ALPHA
2 PROC_B_BETA
3 PROC_C_charlie

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Join Cursor With Table Outside Of Cursor

Sep 25, 2007

part 1

Declare @SQLCMD varchar(5000)
DECLARE @DBNAME VARCHAR (5000)

DECLARE DBCur CURSOR FOR
SELECT U_OB_DB FROM [@OB_TB04_COMPDATA]

OPEN DBCur
FETCH NEXT FROM DBCur INTO @DBNAME


WHILE @@FETCH_STATUS = 0
BEGIN

SELECT @SQLCMD = 'SELECT T0.CARDCODE, T0.U_OB_TID AS TRANSID, T0.DOCNUM AS INV_NO, ' +
+ 'T0.DOCDATE AS INV_DATE, T0.DOCTOTAL AS INV_AMT, T0.U_OB_DONO AS DONO ' +
+ 'FROM ' + @DBNAME + '.dbo.OINV T0 WHERE T0.U_OB_TID IS NOT NULL'
EXEC(@SQLCMD)
PRINT @SQLCMD
FETCH NEXT FROM DBCur INTO @DBNAME

END

CLOSE DBCur
DEALLOCATE DBCur


Part 2

SELECT
T4.U_OB_PCOMP AS PARENTCOMP, T0.CARDCODE, T0.CARDNAME, ISNULL(T0.U_OB_TID,'') AS TRANSID, T0.DOCNUM AS SONO, T0.DOCDATE AS SODATE,
SUM(T1.QUANTITY) AS SOQTY, T0.DOCTOTAL - T0.TOTALEXPNS AS SO_AMT, T3.DOCNUM AS DONO, T3.DOCDATE AS DO_DATE,
SUM(T2.QUANTITY) AS DOQTY, T3.DOCTOTAL - T3.TOTALEXPNS AS DO_AMT
INTO #MAIN
FROM
ORDR T0
JOIN RDR1 T1 ON T0.DOCENTRY = T1.DOCENTRY
LEFT JOIN DLN1 T2 ON T1.DOCENTRY = T2.BASEENTRY AND T1.LINENUM = T2.BASELINE AND T2.BASETYPE = T0.OBJTYPE
LEFT JOIN ODLN T3 ON T2.DOCENTRY = T3.DOCENTRY
LEFT JOIN OCRD T4 ON T0.CARDCODE = T4.CARDCODE
WHERE ISNULL(T0.U_OB_TID,0) <> 0
GROUP BY T4.U_OB_PCOMP, T0.CARDCODE,T0.CARDNAME, T0.U_OB_TID, T0.DOCNUM, T0.DOCDATE, T3.DOCNUM, T3.DOCDATE, T0.DOCTOTAL, T3.DOCTOTAL, T3.TOTALEXPNS, T0.TOTALEXPNS


my question is,
how to join the part 1 n part 2?
is there posibility?

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Oct 3, 2006

Hi all.



I am stuck in a bit of a conundrum for quite a while now, and I hope someone here will help me figure this one out.



So, first things first: let me explain what I need to do. I am
designing a web application that will allow users to consult info
available in a SQL2000 database. The user will enter the search
criterea, and hopefully the web page will show matching results.



The problem is the results shown aren't available per se in the DB, I
need to process the data a bit. I decided to do so on the SQL Server
side, though the use of cursors. So, when a user defines his search
criteria, I run a stored procedure that begins by building a dynamic
sql query and creating a cursor for it. I used a global cursor in order
to do so. It looked something like this:



SET @sqlQuery = ... (build the dinamic sql query)

SET @cursorQuery = 'DECLARE myCursor CURSOR GLOBAL FAST_FORWARD FOR ' + @sqlQuery

EXEC @cursorQuery

OPEN myCursor

FETCH NEXT FROM myCursor INTO ...

CLOSE myCursor

DEALLOCATE myCursor



This works fine, if there's only one instance of the
stored procedure running at a time. Should another user connect to the
site and run a search while someone's at it, it'll fail due to the
atempt to create a cursor with the same name.



My first thought was to make the cursor name unique, which led me to:

...

SET @cursorName = 'myCursor' + @uniqueUserID

SET @cursorQuery = 'DECLARE '+ @cursorName + 'CURSOR FAST_FORWARD FOR ' + @sqlQuery

EXEC @cursorQuery

...



The problem with this is that I can't do a FETCH NEXT FROM @cursorName since
@cursorName is a char variable holding the cursor name, and not a
cursor variable. So to enforce this unique name method the only option
I have is to keep creating dynamic sql queries and exucting them. And
this makes the sp a bitch to develop and maintain, and I'm guessing it
doesn't make it very performant.



So I moved on to my second idea: local cursor variables. The problem with
this is that if I create a local cursor variable by executing a dynamic
query, I can't extract it from the EXEC (or sp_executesql) context, as
it offers no output variable.


I guess my concrete questions are:


Is it possible to execute a dynamic sql query and extract a (cursor) variable from it?Is it possible to populate a local cursor variable with a global cursor, by providing the global cursor's name?Can I create a local cursor variable for a dynamic sql query? How?



Anybody sees another way arround this?Thanks in advance,

Carlos

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Apr 16, 2015

I need to find all uses of special characters in a database. I used the following code to do this:

USE dbName
GO
IF OBJECT_ID('tempdb.dbo.#Results') IS NOT NULL DROP TABLE #Results
GO

[code]...

This will check all tables in the database, but if you want to check specific tables you can uncomment the line in the where clause and specify tables to be checked. The query will return any text fields that have any characters other than letters, numbers or spaces.

This code works fine for me because all the tables in my database have single column primary keys. However I know how much Jeff Moden hates cursors or RBAR queries, so my question is could this have been done by any method other than using a cursor?

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Oct 5, 2004

I'm new to cursors, and I'm not sure what's wrong with this code, it run for ever and when I stop it I get cursor open errors




declare Q cursor for
select systudentid from satrans


declare @id int

open Q
fetch next from Q into @id
while @@fetch_status = 0
begin

declare c cursor for

Select
b.ssn,
SaTrans.SyStudentID,
satrans.date,
satrans.type,
SaTrans.SyCampusID,
Amount = Case SaTrans.Type
When 'P' Then SaTrans.Amount * -1
When 'C' Then SaTrans.Amount * -1
Else SaTrans.Amount END

From SaTrans , systudent b where satrans.systudentid = b.systudentid

and satrans.systudentid = @id




declare @arbalance money, @type varchar, @ssn varchar, @amount money, @systudentid int, @transdate datetime, @sycampusid int, @before money

set @arbalance = 0
open c
fetch next from c into @ssn, @systudentid, @transdate, @type, @sycampusid, @amount

while @@fetch_status = 0
begin

set @arbalance = @arbalance + @amount
set @before = @arbalance -@amount

insert c2000_utility1..tempbalhistory1
select @systudentid systudentid, @sycampusid sycampusid, @transdate transdate, @amount amount, @type type, @arbalance Arbalance, @before BeforeBalance
where( convert (int,@amount) <= -50
or @amount * -1 > @before * .02)
and @type = 'P'




fetch next from c into @ssn, @systudentid, @transdate, @type, @sycampusid, @amount
end
close c
deallocate c
fetch next from Q into @id

end
close Q
deallocate Q


select * from c2000_utility1..tempbalhistory1
truncate table c2000_utility1..tempbalhistory1

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Jun 23, 2006

Hello Everyone,I have a very complex performance issue with our production database.Here's the scenario. We have a production webserver server and adevelopment web server. Both are running SQL Server 2000.I encounted various performance issues with the production server with aparticular query. It would take approximately 22 seconds to return 100rows, thats about 0.22 seconds per row. Note: I ran the query in singleuser mode. So I tested the query on the Development server by taking abackup (.dmp) of the database and moving it onto the dev server. I ranthe same query and found that it ran in less than a second.I took a look at the query execution plan and I found that they we'rethe exact same in both cases.Then I took a look at the various index's, and again I found nodifferences in the table indices.If both databases are identical, I'm assumeing that the issue is relatedto some external hardware issue like: disk space, memory etc. Or couldit be OS software related issues, like service packs, SQL Serverconfiguations etc.Here's what I've done to rule out some obvious hardware issues on theprod server:1. Moved all extraneous files to a secondary harddrive to free up spaceon the primary harddrive. There is 55gb's of free space on the disk.2. Applied SQL Server SP4 service packs3. Defragmented the primary harddrive4. Applied all Windows Server 2003 updatesHere is the prod servers system specs:2x Intel Xeon 2.67GHZTotal Physical Memory 2GB, Available Physical Memory 815MBWindows Server 2003 SE /w SP1Here is the dev serers system specs:2x Intel Xeon 2.80GHz2GB DDR2-SDRAMWindows Server 2003 SE /w SP1I'm not sure what else to do, the query performance is an order ofmagnitude difference and I can't explain it. To me its is a hardware oroperating system related issue.Any Ideas would help me greatly!Thanks,Brian T*** Sent via Developersdex http://www.developersdex.com ***

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Jul 20, 2005

I having a difficult time here trying to figure out what to do here.I need a way to scroll through a recordset and display the resultswith both forward and backward movement on a web page(PHP usingADO/COM)..I know that if I use a client side cursor all the records get shovedto the client everytime that stored procedure is executed..if thisdatabase grows big wont that be an issue?..I know that I can set up a server side cursor that will only send therecord I need to the front end but..Ive been reading around and a lot of people have been saying never touse a server side cursor because of peformance issues.So i guess im weighing network performance needs with the client sidecursor vs server performance with the server side cursor..I am reallyconfused..which one should I use?-Jim

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Jun 22, 2006

Hello Everyone,I have a very complex performance issue with our production database.Here's the scenario. We have a production webserver server and adevelopment web server. Both are running SQL Server 2000.I encounted various performance issues with the production server witha particular query. It would take approximately 22 seconds to return100 rows, thats about 0.22 seconds per row. Note: I ran the query insingle user mode. So I tested the query on the Development server bytaking a backup (.dmp) of the database and moving it onto the devserver. I ran the same query and found that it ran in less than asecond.I took a look at the query execution plan and I found that they we'rethe exact same in both cases.Then I took a look at the various index's, and again I found nodifferences in the table indices.If both databases are identical, I'm assumeing that the issue isrelated to some external hardware issue like: disk space, memory etc.Or could it be OS software related issues, like service packs, SQLServer configuations etc.Here's what I've done to rule out some obvious hardware issues on theprod server:1. Moved all extraneous files to a secondary harddrive to free up spaceon the primary harddrive. There is 55gb's of free space on the disk.2. Applied SQL Server SP4 service packs3. Defragmented the primary harddrive4. Applied all Windows Server 2003 updatesHere is the prod servers system specs:2x Intel Xeon 2.67GHZTotal Physical Memory 2GB, Available Physical Memory 815MBWindows Server 2003 SE /w SP1Here is the dev serers system specs:2x Intel Xeon 2.80GHz2GB DDR2-SDRAMWindows Server 2003 SE /w SP1I'm not sure what else to do, the query performance is an order ofmagnitude difference and I can't explain it. To me its is a hardware oroperating systemrelated issue.Any Ideas would help me greatly!Thanks,Brian T

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Apr 4, 2000

Hi,
I have just upgrade my sql 6.5 to 7.0 version. This sql box (compaq proliant 5500) has 1 gig ram and 4 pentium pro processors and smart array controller. There are about 200 users hit on that server constantly. I configured this server according compaq white paper and Microsoft recommendation; however, I am still suffering huge performance hit. Then I setup performance monitor to see what is happening. What I see is all of 4 processors are at 70% processor time constantly. What I heard is sql 7.0 runs much better on pentium III processors. Is that true? Or you have any recommendations??


Help!!
Thanks!!

Jim Zhong

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