Which one is faster cursor or while loop?
While SQL While loop is quicker than a cursor, reason found that cursor is defined by DECLARE CURSOR. Every emphasis of the loop will be executed inside system memory and consuming required server assets.
How can I speed up my UPDATE query?
The fastest way to speed up the update query is to replace it with a bulk-insert operation. It is a minimally logged operation in simple and Bulk-logged recovery model. This can be done easily by doing a bulk-insert in a new table and then rename the table to original one.
When is a cursor better than a set based query?
There are two places where a cursor is at an advantage: You are updating a large data set in a database where locking rows is not acceptable (during production hours maybe). A set based update has a possibility of locking a table for several seconds (or minutes), where a cursor (if written correctly) does not.
How to speed up a simple update query?
UPDATE PF SET PF.SourceId = AAON.NewSourceId FROM AA..Pub_ArticleFaculty PF WITH (NOLOCK) INNER JOIN AA2..ArticleAuthorOldNew AAON WITH (NOLOCK) ON AAON.OldFullSourceId = PF.SourceId In my experience, looping your update so that it acts on small a numbers of rows each iteration is a good way to go.
Which is faster update by row or bulk update?
It’s a faster update than a row by row operation, but this is best used when updating limited rows. A bulk update is an expensive operation in terms of query cost, because it takes more resources for the single update operation. It also takes time for the update to be logged in the transaction log.
When to use cursor.execute for multiple inserts?
Using this for multiple INSERT statements should be just fine: If you need to execute a series of disparate statements like from a script, then for most cases you can just split the statements on ; and feed each statement to cursor.execute () separately.