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From: ernest_it@hotmail.com (ernest_it@hotmail.com)
X-Newsgroups: comp.databases.postgresql.sql
Subject: create index
Date: 18 Nov 2002 22:44:05 -0800
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i don't know how to create the index about the following statement.


SELECT b.screen_id AS screen_id, b.name AS screen_name
FROM tbl_showlog AS a CROSS JOIN
tbl_screen AS b CROSS JOIN
tbl_company AS c
WHERE a.screen_id = b.screen_id
AND b.company_id = c.company_id
AND c.company_id = 1
AND c.is_active = 1
GROUP BY b.screen_id, b.name
ORDER BY b.screen_id

many thx!