Views have been introduced MySql. Lets see how they can be created and used.
Views are nothing but subset of a table in a database.
You may not want all tabular data for a particular purpose. You may want to certain users not to see some part of the tabular data.
Views comes to your rescue in such a situation.
general syntax from mysql manual
[code lang=”SQL”]
CREATE
[OR REPLACE]
[ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}]
[DEFINER = { user | CURRENT_USER }]
[SQL SECURITY { DEFINER | INVOKER }]
VIEW view_name [(column_list)]
AS select_statement
[WITH [CASCADED | LOCAL] CHECK OPTION]
[/code]
A very good example straight from the manual.
[code lang=”SQL”]
mysql> CREATE TABLE t (qty INT, price INT);
mysql> INSERT INTO t VALUES(3, 50);
mysql> CREATE VIEW v AS SELECT qty, price, qty*price AS value FROM t;
mysql> SELECT * FROM v;
[/code]
+------+-------+-------+ | qty | price | value | +------+-------+-------+ | 3 | 50 | 150 | +------+-------+-------+
