Re: Tsearch2 Initial Search Speed
От | Matthew Wakeling |
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Тема | Re: Tsearch2 Initial Search Speed |
Дата | |
Msg-id | Pine.LNX.4.64.0806171202130.3987@aragorn.flymine.org обсуждение исходный текст |
Ответ на | Re: Tsearch2 Initial Search Speed (Howard Cole <howardnews@selestial.com>) |
Ответы |
Re: Tsearch2 Initial Search Speed
|
Список | pgsql-performance |
On Tue, 17 Jun 2008, Howard Cole wrote: > I think I may have answered my own question partially, the problem may be how > I structure the query. > > Original statement: > > "Nested Loop (cost=4.40..65.08 rows=16 width=8)" > " -> Function Scan on q (cost=0.00..0.01 rows=1 width=32)" > " -> Bitmap Heap Scan on email (cost=4.40..64.87 rows=16 width=489)" > " Filter: (email.fts @@ q.q)" > " -> Bitmap Index Scan on email_fts_index (cost=0.00..4.40 rows=16 width=0)" > " Index Cond: (email.fts @@ q.q)" > > Second statement: > > "Bitmap Heap Scan on email (cost=4.40..64.91 rows=16 width=8)" > " Filter: (fts @@ '''howard'''::tsquery)" > " -> Bitmap Index Scan on email_fts_index (cost=0.00..4.40 rows=16 width=0)" > " Index Cond: (fts @@ '''howard'''::tsquery)" As far as I can see, that shouldn't make any difference. Both queries still do the bitmap heap scan, and have almost exactly the same cost. Matthew -- Lord grant me patience, and I want it NOW!
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