Mega Code Archive
Create a view in which the difference between the number of sets won and the number of sets lost are recorded
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for each match.
mysql>
mysql> CREATE TABLE MATCHES(
-> MATCHNO INTEGER NOT NULL,
-> TEAMNO INTEGER NOT NULL,
-> PLAYERNO INTEGER NOT NULL,
-> WON SMALLINT NOT NULL,
-> LOST SMALLINT NOT NULL,
-> PRIMARY KEY (MATCHNO)
-> );
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql> INSERT INTO MATCHES VALUES (1, 1, 6, 3, 1);
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO MATCHES VALUES (4, 1, 44, 3, 2);
Query OK, 1 row affected (0.00 sec)
mysql>
mysql>
mysql>
mysql> CREATE VIEW NUMBER_SETS (MATCHNO, DIFFERENCE) AS
-> SELECT MATCHNO, ABS(WON - LOST)
-> FROM MATCHES;
mysql>
mysql>
mysql> SELECT *
-> FROM NUMBER_SETS;
+---------+------------+
| MATCHNO | DIFFERENCE |
+---------+------------+
| 1 | 2 |
| 4 | 1 |
+---------+------------+
2 rows in set (0.00 sec)
mysql>
mysql> drop table matches;
Query OK, 0 rows affected (0.00 sec)
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