To find a value and save it in a variable : Variable « Select Clause « SQL / MySQL






  1. SQL / MySQL
  2. Select Clause
  3. Variable

To find a value and save it in a variable

       
mysql>
mysql> CREATE TABLE standings1
    -> (
    ->  team    CHAR(20),               # team name
    ->  wins    INT,                    # number of wins
    ->  losses  INT                             # number of losses
    -> );
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Winnipeg',37,20);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Crookston',31,25);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Fargo',30,26);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Grand Forks',28,26);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Devils Lake',19,31);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO standings1 (team, wins, losses) VALUES ('Cavalier',15,32);
Query OK, 1 row affected (0.00 sec)

mysql>
mysql> SELECT @wl_diff := MAX(wins-losses) FROM standings1;
+------------------------------+
| @wl_diff := MAX(wins-losses) |
+------------------------------+
|                           17 |
+------------------------------+
1 row in set (0.00 sec)

mysql>
mysql> drop table standings1;
Query OK, 0 rows affected (0.00 sec)








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