diff options
| author | Bruce Momjian | 2003-05-28 04:35:28 +0000 |
|---|---|---|
| committer | Bruce Momjian | 2003-05-28 04:35:28 +0000 |
| commit | a2b498c291d9c21474f128f37c89482908bf35b0 (patch) | |
| tree | a649c8190581da1ad1a77a513bf75f19e1e1e372 /doc/FAQ | |
| parent | a6f01d1aa684ef6aa0972a11648a7725a309c471 (diff) | |
Add info about selecting a random row.
Diffstat (limited to 'doc/FAQ')
| -rw-r--r-- | doc/FAQ | 12 |
1 files changed, 9 insertions, 3 deletions
@@ -1,7 +1,7 @@ Frequently Asked Questions (FAQ) for PostgreSQL - Last updated: Mon May 26 15:25:04 EDT 2003 + Last updated: Wed May 28 00:35:16 EDT 2003 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) @@ -58,7 +58,7 @@ Operational Questions 4.1) What is the difference between binary cursors and normal cursors? - 4.2) How do I SELECT only the first few rows of a query? + 4.2) How do I SELECT only the first few rows of a query? A random row? 4.3) How do I get a list of tables or other things I can see in psql? 4.4) How do you remove a column from a table, or change it's data type? @@ -627,7 +627,7 @@ See the DECLARE manual page for a description. - 4.2) How do I SELECT only the first few rows of a query? + 4.2) How do I SELECT only the first few rows of a query? A random row? See the FETCH manual page, or use SELECT ... LIMIT.... @@ -637,6 +637,12 @@ evaluate only the first few records requested, or the entire query may have to be evaluated until the desired rows have been generated. + To SELECT a random row, use: + SELECT col + FROM tab + ORDER BY random() + LIMIT 1; + 4.3) How do I get a list of tables or other things I can see in psql? You can read the source code for psql in file |