Cursor.. cmds don’t seem to update until everything has finished

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Home » SQL Server 2005 » T-SQL (SS2K5) » Cursor.. cmds don’t seem to update until...

Cursor.. cmds don’t seem to update until everything has finished

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Edward-445599

Posted Wednesday, March 06, 2013 6:30 AM

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I have a cursor and in that cursor
I have a number of commands like

EXEC (@command)
print 'ghgfhgfhgfh’
insert mytable values (@aaaaa)

I would expect that with each loop of the cursor I would see the results of the print statement and a value inserted into mytable.

But I don’t it seems that the whole cursor has to be processed then all print statements appear and all the inserts occur all at once.

I need to see how far and fast the cursor is processing, also I am worried that none of the memory is being freed up until the whole cursor has finished

Any help?

Many thanks

Post #1427345

ChrisM@Work

Posted Wednesday, March 06, 2013 6:41 AM

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Try using this instead of print, which is buffered:
raiserror ('My Print Statement', 10,1) with nowait

Your inserts may be uncommitted until the cursor loop has completed, in which case you could still see some data using the NOLOCK query hint.

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden
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Post #1427353

Lowell

Posted Wednesday, March 06, 2013 6:46 AM

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inside a cursor, that's normal; what you want to do instead of print is raise a low level error inside via RAISERROR the cursor so you can see things as it happens.

errors with NOWAIT are immediately visible in the results pane.
example:

--print error immediately in batch
declare @i int,
        @err varchar(100)
--set @i=1
while 0=0
begin
SET @err = 'Progress So Far: Step ' + convert(varchar(30),ISNULL(@i,1)) + ' completed.'
raiserror (@err,0,1) with nowait
waitfor delay '00:00:02'
set @i=ISNULL(@i,1) + 1
end

Lowell

--There is no spoon, and there's no default ORDER BY in sql server either.
Actually, Common Sense is so rare, it should be considered a Superpower. --my son

Post #1427358

Sean Lange

Posted Wednesday, March 06, 2013 7:44 AM

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Maybe an even better approach would be to remove the cursor and do your inserts set based? Cursors are notoriously slow and over used. They have their place but very rarely does doing some inserts like you are describing require a cursor.

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