问题
I have a trigger that is used to perform some auditing tasks when changes are made to a table. Within this trigger there is a WHILE loop, and in the loop there is a cursor that is declared, used, closed and then deallocated before the next iteration of the loop.
When I call a stored procedure that changes the table and in turn causes the trigger to run, and I do this from within the Management Studio, all works as expected.
However, when this stored procedure is called from within my Java web application, I get an error: "A cursor with the name ... already exists".
Is there a reason why this stored procedure would work when I execute it manually, and not work when run from the web application?
回答1:
It sounds like you might be using GLOBAL cursors, which could cause problems like this.
If you must use cursors:
If you can, use LOCAL cursors in all your code. e.g. declare cursor using the "LOCAL" keyword, like this:
DECLARE yourcursor CURSOR LOCAL ...
回答2:
You can also try this
IF CURSOR_STATUS('global', 'Cursorname') >= -1
BEGIN
CLOSE Cursorname
DEALLOCATE Cursorname
END
回答3:
Sounds a little like it is being called by multiple threads and therefore already exists when the second thread tries to use the name. You might try naming your cursor dynamically with a GUID in the name etc. I would not recommend this approach.
I suggest you remove the cursor from your trigger code if at all possible in favour of a set based approach. Overhead of using a cursor within the trigger must be pretty high.
来源：https://stackoverflow.com/questions/6735719/a-cursor-with-the-name-already-exists-sql-server-2008