/*
mysql> /* find out how many Birds each owner has: */ mysql> SELECT owner, COUNT(*) FROM Bird GROUP BY owner; +-------+----------+ | owner | COUNT(*) | +-------+----------+ | Joe | 1 | | Yin | 2 | +-------+----------+ 2 rows in set (0.01 sec)
*/ Drop table Bird;
CREATE TABLE Bird ( name VARCHAR(20), owner VARCHAR(20), species VARCHAR(20), sex CHAR(1), birth DATE, death DATE ); INSERT INTO Bird VALUES ('BlueBird','Joe','Car','f','1999-03-30',NULL); INSERT INTO Bird VALUES ('RedBird','Yin','Bus','m','1979-04-30',1998-01-30); INSERT INTO Bird VALUES ('RedBird','Yin','Bus','m','1998-01-30',NULL);
/* find out how many Birds each owner has: */
SELECT owner, COUNT(*) FROM Bird GROUP BY owner;
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