The CREATE VIEW statement creates a
new view (see Section 12.1.20, “CREATE VIEW Syntax”). To alter the
definition of a view or drop a view, use
ALTER VIEW (see
Section 12.1.9, “ALTER VIEW Syntax”), or DROP
VIEW (see Section 12.1.31, “DROP VIEW Syntax”).
A view can be created from many kinds of
SELECT statements. It can refer to
base tables or other views. It can use joins,
UNION, and subqueries. The
SELECT 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 | +------+-------+-------+

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