-- Nibble update DECLARE @RowsToUpdate int SELECT @RowsToUpdate = COUNT(*) FROM TableToUpdate WHERE myColumn = '' DECLARE @Progress int SET @Progress = 0 WHILE @Progress < @RowsToUpdate BEGIN UPDATE TOP (1000) TableToUpdate SET myColumn = cast(rtrim(column1) as varchar(150)) + ' \\ ' + cast(rtrim(column2) as varchar(150)) FROM TableToUpdate WHERE myColumn = '' SET @Progress = @Progress + @@RowCount END
Wednesday, March 12, 2014
TSQL - Nibble Update
I've often had to utilize a 'Nibble Delete' approach to removing a large volume of data. Doing so prevents record locking and I/O requests overwhelming a system. I had to do the same with an UPDATE statement today, to combine a couple of columns. A generic version of the script is below.
Posted by r5d4 at 22:41