The plan used the way to bypass 'order by' via index scan backward. The
query should scan tables through the index and do nl join the other tables
while it finds 10 rows that meet the condition MCL.ctid = '01010002759'.
The problem is the rows that meets your condition is very rarely founded so
the
wangqi wrote:
> An SQL execution is very slow.
> What can I do to makes it faster。
Without knowing more about the version of PostgreSQL, your PostgreSQL
configuration, your schema (including indexes), and your hardware,
it's hard to give advice.
http://wiki.postgresql.org/wiki/SlowQueryQuest
