MySQL中怎么创建视图
发布时间：2022-02-10 13:20:14 所属栏目：MySql教程 来源：互联网
导读：MySQL中怎么创建视图，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。 MariaDB [test] CREATE TABLE t (qty INT, price INT); Query OK, 0 rows affected (0.15 sec) MariaDB [test] INS
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MySQL中怎么创建视图，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。 MariaDB [test]> CREATE TABLE t (qty INT, price INT); Query OK, 0 rows affected (0.15 sec) MariaDB [test]> INSERT INTO t VALUES(3, 50); Query OK, 1 row affected (0.01 sec) --创建视图 MariaDB [test]> CREATE VIEW v AS SELECT qty, price, qty*price AS value FROM t; Query OK, 0 rows affected (0.09 sec) MariaDB [test]> SELECT * FROM v; +------+-------+-------+ | qty | price | value | +------+-------+-------+ | 3 | 50 | 150 | +------+-------+-------+ 1 row in set (0.00 sec) MariaDB [test]> explain select * from v; +------+-------------+-------+------+---------------+------+---------+------+------+-------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +------+-------------+-------+------+---------------+------+---------+------+------+-------+ | 1 | SIMPLE | t | ALL | NULL | NULL | NULL | NULL | 1 | | +------+-------------+-------+------+---------------+------+---------+------+------+-------+ 1 row in set (0.00 sec) --查看视图状态 MariaDB [test]> show table status from test like 'v'G *************************** 1. row *************************** Name: v Engine: NULL Version: NULL Row_format: NULL Rows: NULL Avg_row_length: NULL Data_length: NULL Max_data_length: NULL Index_length: NULL Data_free: NULL Auto_increment: NULL Create_time: NULL Update_time: NULL Check_time: NULL Collation: NULL Checksum: NULL Create_options: NULL Comment: VIEW 1 row in set (0.00 sec) --查看创建语句 MariaDB [test]> show create view vG *************************** 1. row *************************** View: v Create View: CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v` AS select `t`.`qty` AS `qty`,`t`.`price` AS `price`,(`t`.`qty` * `t`.`price`) AS `value` from `t` character_set_client: utf8 collation_connection: utf8_general_ci MariaDB [test]> select * from information_schema.views where table_name = 'v'G *************************** 1. row *************************** TABLE_CATALOG: def TABLE_SCHEMA: test TABLE_NAME: v VIEW_DEFINITION: select `test`.`t`.`qty` AS `qty`,`test`.`t`.`price` AS `price`,(`test`.`t`.`qty` * `test`.`t`.`price`) AS `value` from `test`.`t` CHECK_OPTION: NONE IS_UPDATABLE: YES DEFINER: root@localhost SECURITY_TYPE: DEFINER CHARACTER_SET_CLIENT: utf8 COLLATION_CONNECTION: utf8_general_ci ALGORITHM: UNDEFINED 1 row in set (0.02 sec) 看完上述内容，你们掌握MySQL中怎么创建视图的方法了吗？ （编辑：云计算网_宿迁站长网） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |
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