When should we use the sql cursor

Question

Hi everyone, tell me when should I use the cursor?

thanks Saj

Answer 1

Ideally, as little as possible. Cursors have fairly high processing overheads.

Or when

• The process you are running cannot be rewritten as a collection-based operation. (For example, call DBCC DBREINDEX in turn in the table list)
• Set-based operation has the worst asymptotic complexity. To run aggregates, a solution based on a set has quadratic complexity, while the cursor's workload grows linearly.

SQL CLR- , .

Answer 2

, : http://wiki.lessthandot.com/index.php/Cursors_and_How_to_Avoid_Them

, , .

Answer 3

Oracle:

EXPLICIT CURSORS WITH IN SQL * FORMS 3.0
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~

. , , .

- SQL. PL/SQL ( 2-16):

, :

• ,
• , .

SELECT .

, . , . , .