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

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

Edward-445599

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March 6, 2013 at 6:30 am

#394324

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

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ChrisM@Work SSC Guru Points: 186127 More actions · Answer 1

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.

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Lowell SSC Guru Points: 323518 More actions · Answer 2

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

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Sean Lange SSC Guru Points: 286590 More actions · Answer 3

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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