Topic: Performance & Tuning >> count(*) and count(1)
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| Title: count(*) and count(1) |
| Thunderchicken |
Posted: Dec 26, 2002 04:12:00 PM |
Total Post: 1
Joined: Jan, 2003
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Hi All,
Is there any performance issues when running a select count (*) instead of select count (1) or select count (rowid) statement?
Thanks,
Miller
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 tonny_2003 |
| Posted: Dec 26, 2002 04:17:00 PM |  |
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Total Post: 6
Joined: Jan, 2003
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I think count (*) will be a full table scan irrespective of the indexes present on
the table whereas Count (1) will only scan the index space provided the column1 is indexed. So count (1) should be faster since less bytes will be read.
Thanks,
Vimal
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| vasu |
| Posted: Dec 26, 2002 04:27:00 PM | |
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Total Post: 50
Joined: Jan, 2003
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Probably count(*) is less performing than count(1).
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