Mega Code Archive
Working with Per-Group and Overall Summary Values Simultaneously
<![CDATA[
mysql>
mysql> CREATE TABLE mytable
-> (
-> rec_id INT UNSIGNED NOT NULL AUTO_INCREMENT,
-> name VARCHAR(20) NOT NULL,
-> trav_date DATE NOT NULL,
-> miles INT NOT NULL,
-> PRIMARY KEY (rec_id)
-> );
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> INSERT INTO mytable (name,trav_date,miles)
-> VALUES
-> ('Ben','2010-11-30',152),
-> ('Suzi','2010-11-29',391),
-> ('Henry','2010-11-29',300),
-> ('Henry','2010-11-27',96),
-> ('Ben','2010-11-29',131),
-> ('Henry','2010-11-26',115),
-> ('Suzi','2010-12-02',502),
-> ('Henry','2010-12-01',197),
-> ('Ben','2010-12-02',79),
-> ('Henry','2010-11-30',203)
-> ;
Query OK, 10 rows affected (0.00 sec)
Records: 10 Duplicates: 0 Warnings: 0
mysql>
mysql>
mysql> SELECT @total := SUM(miles) AS 'total miles' FROM mytable;
+-------------+
| total miles |
+-------------+
| 2166 |
+-------------+
1 row in set (0.00 sec)
mysql>
mysql>
mysql> SELECT name,
-> SUM(miles) AS 'miles/driver',
-> (SUM(miles)*100)/@total AS 'percent of total miles'
-> FROM mytable GROUP BY name;
+-------+--------------+------------------------+
| name | miles/driver | percent of total miles |
+-------+--------------+------------------------+
| Ben | 362 | 16.7128 |
| Henry | 911 | 42.0591 |
| Suzi | 893 | 41.2281 |
+-------+--------------+------------------------+
3 rows in set (0.00 sec)
mysql>
mysql> drop table mytable;
Query OK, 0 rows affected (0.00 sec)
mysql>
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