Can I reset cursor's position to the beginning?

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感动是毒
感动是毒 2020-12-29 22:27

As in the topic. Can I simply reset cursor\'s position to the beginning in Transact-SQL, so it can run again over the table? I want to reset it in the following context:

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  • 2020-12-29 23:04

    Another option that can be used that doesn't force you to change the type of cursor is simply to close the cursor and re-open it:

    CLOSE user_cursor
    OPEN user_cursor
    

    But the scroll option will be cheaper in terms of resource usage, if that's a change you can accept.

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  • 2020-12-29 23:18

    Use cursor loops and its taken care of for you...

    cursor c_something IS
       select * from somewhere
    
    BEGIN
    
        for some_row in c_something LOOP
            -- do stuff with some_row.COLUMN;
        END LOOP; -- this closes the cursor for you when it has gone all the way through
    
        -- do other stuff
    
        for some_row in c_something LOOP -- opens the cursor again from the top
            -- do stuff with some_row.COLUMN;
        END LOOP;
    
    END;
    
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  • 2020-12-29 23:22

    you need to declare your cursor as scroll, like this

    declare c scroll cursor for (select statement); 
    

    then at any time for locating to the first just use the following

    fetch first from c;
    
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  • 2020-12-29 23:23

    The data retrieved by the cursor will not change.

    STATIC

    Defines a cursor that makes a temporary copy of the data to be used by the cursor. All requests to the cursor are answered from this temporary table in tempdb; therefore, modifications made to base tables are not reflected in the data returned by fetches made to this cursor, and this cursor does not allow modifications.

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