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author | Bruce Momjian <bruce@momjian.us> | 2003-01-17 17:15:14 +0000 |
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committer | Bruce Momjian <bruce@momjian.us> | 2003-01-17 17:15:14 +0000 |
commit | d12be5c37b43d591d7dd2847519376f83b43f7a5 (patch) | |
tree | a1d7372670e4e85336d80c273bf26b58fcf1975a /doc/FAQ | |
parent | 3c731e0ed767da7695598ae1d9792e4b6d9b0366 (diff) | |
download | postgresql-d12be5c37b43d591d7dd2847519376f83b43f7a5.tar.gz postgresql-d12be5c37b43d591d7dd2847519376f83b43f7a5.zip |
Add section on testing index scan.
Diffstat (limited to 'doc/FAQ')
-rw-r--r-- | doc/FAQ | 6 |
1 files changed, 5 insertions, 1 deletions
@@ -1,7 +1,7 @@ Frequently Asked Questions (FAQ) for PostgreSQL - Last updated: Sun Jan 12 13:36:11 EST 2003 + Last updated: Fri Jan 17 12:15:04 EST 2003 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) @@ -749,6 +749,10 @@ ORDER BY col [ DESC ] LIMIT 1; + If you believe the optimizer is incorrect in choosing a sequential + scan, use SET enable_seqscan TO 'off' and run tests to see if an index + scan is indeed faster. + When using wild-card operators such as LIKE or ~, indexes can only be used in certain circumstances: * The beginning of the search string must be anchored to the start |