Subject | ORDER BY with LPAD is to slow |
---|---|
Author | danyschaer |
Post date | 2008-06-19T12:20:30Z |
Hi All;
I am using FB 2.1, and I have found that LPAD slows down (60 seconds or
more for 30k records) a lot when used in a order by clause:
select "EXP1" from "PROC" order by LPAD(lower(trim("EXP1")),18)
or
select LPAD(lower(trim("EXP1")),18) as "XX" from "PROC" order by "XX"
But, it is very fast (0 seconds) if I do not use it in the order by
clause:
select LPAD(lower(trim("EXP1")),18) from "PROC"
Why is this?.
Thank you!
Dany
I am using FB 2.1, and I have found that LPAD slows down (60 seconds or
more for 30k records) a lot when used in a order by clause:
select "EXP1" from "PROC" order by LPAD(lower(trim("EXP1")),18)
or
select LPAD(lower(trim("EXP1")),18) as "XX" from "PROC" order by "XX"
But, it is very fast (0 seconds) if I do not use it in the order by
clause:
select LPAD(lower(trim("EXP1")),18) from "PROC"
Why is this?.
Thank you!
Dany