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How To Divide Query Output into Groups
How To Divide Query Output into Groups? - MySQL FAQs - SQL SELECT Query Statements with GROUP BY
✍: FYIcenter.com
You can divide query output into multiple groups with the GROUP BY clause. It allows you specify a column as the grouping criteria, so that rows with the same value in that column will be considered as a single group. When the GROUP BY clause is specified, the select statement can only be used to return group level information. The following script gives you a good GROUP BY example:
mysql> SELECT tag, COUNT(*), MIN(created), AVG(counts) FROM fyi_links GROUP BY tag; +------+----------+---------------------+-------------+ | tag | COUNT(*) | MIN(created) | AVG(counts) | +------+----------+---------------------+-------------+ | DBA | 3 | 2005-01-01 00:00:00 | 3.6667 | | DEV | 2 | 2004-01-01 00:00:00 | 4.0000 | | SQA | 2 | 2003-01-01 00:00:00 | 7.0000 | +------+----------+---------------------+-------------+ 3 rows in set (0.07 sec)
2007-05-11, 7474👍, 0💬
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