Re: [HACKERS] Solution for LIMIT cost estimation

At 10:43 16/02/00 -0500, Tom Lane wrote:
>Philip Warner <pjw@rhyme.com.au> writes:
>>> A possible answer is to define OFFSET/LIMIT in DECLARE CURSOR as
>>> being simply a hint to the optimizer about how much of the query
>>> result will actually get fetched.  
>
>> This seems a good approach until cursors are fixed. But is there a plan to
>> make cursors support LIMIT properly? Do you know why they ignore the LIMIT
>> clause?
>
>Should they obey LIMIT?  MOVE/FETCH seems like a considerably more
>flexible interface, so I'm not quite sure why anyone would want to
>use LIMIT in a cursor.

I agree; but see below.


>Still, it seems kind of inconsistent that cursors ignore LIMIT.
>I don't know for sure why it was done that way.

It's the inconsistency that bothers me: if I run a SELECT statement, then
put it in a cursor, I should get the same rows returned. Ths current
behaviour should probably be considered a bug.



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