MySQL :: MySQL 8.4 Reference Manual :: 27.5.1 View Syntax (original) (raw)

27.5.1 View Syntax

The CREATE VIEW statement creates a new view (see Section 15.1.23, “CREATE VIEW Statement”). To alter the definition of a view or drop a view, useALTER VIEW (seeSection 15.1.11, “ALTER VIEW Statement”), or DROP VIEW (see Section 15.1.35, “DROP VIEW Statement”).

A view can be created from many kinds ofSELECT statements. It can refer to base tables or other views. It can use joins,UNION, and subqueries. TheSELECT need not even refer to any tables. The following example defines a view that selects two columns from another table, as well as an expression calculated from those columns:

mysql> CREATE TABLE t (qty INT, price INT);
mysql> INSERT INTO t VALUES(3, 50), (5, 60);
mysql> CREATE VIEW v AS SELECT qty, price, qty*price AS value FROM t;
mysql> SELECT * FROM v;
+------+-------+-------+
| qty  | price | value |
+------+-------+-------+
|    3 |    50 |   150 |
|    5 |    60 |   300 |
+------+-------+-------+
mysql> SELECT * FROM v WHERE qty = 5;
+------+-------+-------+
| qty  | price | value |
+------+-------+-------+
|    5 |    60 |   300 |
+------+-------+-------+