![]() ![]() ![]() GO CREATE TABLE Funcionarios (ID Int IDENTITY ( 1, 1 ) PRIMARY KEY , IF OBJECT_ID ( 'Funcionarios' ) IS NOT NULL DROP TABLE Funcionarios In my experience it has proved to be the fastest option in general overall in real life use cases and can have the least amount of CPU usage as well. As such in a heavily used environment it can actually be much faster than any of the other options. Where as a STATIC cursor only hits the table once and all further actions are against the copy in tempdb which has no need for dealing with concurrency options. This can be from both sides meaning that it can cause blocking and be blocked. Even LOCAL FAST_FORWARD cursors go back to the original source with new fetches and do take locks and latches which can interfere with a highly concurrent operation. ![]() One thing I want to point out is that even though Static may not have the smallest footprint out of the cursors and might be slightly slower under these conditions it can be dramatically faster in a heavy use / high concurrency one. I am just now seeing this post so forgive me for the late reply. This was not the case again we see a roughly 5X hit on tempdb usage with the default cursor and the one with only LOCAL specified:įor years I have been stressing that the following option should always be specified for your cursors: Since the definition of a static cursor means that it copies the entire result to tempdb, and it is actually expressed in sys.dm_exec_cursors as SNAPSHOT, I expected the hit on tempdb pages to be higher with all static variants of the cursor. The best combination here was LOCAL FAST_FORWARD: So I simply restarted before each cold cache test, measuring the performance counter Total Server Memory (KB) before and after each test. I also wanted to measure the additional memory that SQL Server would request when fulfilling each cursor type. Quite arguably the most important and common measure is, "how long did it take?" Well, it took almost five times as long to run a cursor with the default options (or with only LOCAL specified), compared to specifying either STATIC or FAST_FORWARD: ![]() OPEN c FETCH c INTO WHILE ( = 0 ) BEGIN SET += 1 - meaningless operation FETCH c INTO END CLOSE c DEALLOCATE c Results objects AS c1ĬROSS JOIN ( SELECT TOP 500 name FROM sys. DECLARE INT = 1 DECLARE c CURSOR - LOCAL - LOCAL STATIC - LOCAL FAST_FORWARD - LOCAL STATIC READ_ONLY FORWARD_ONLY FOR SELECT c1. ![]()
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