大橙子网站建设,新征程启航
为企业提供网站建设、域名注册、服务器等服务
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。
10年积累的成都做网站、成都网站制作经验,可以快速应对客户对网站的新想法和需求。提供各种问题对应的解决方案。让选择我们的客户得到更好、更有力的网络服务。我虽然不认识你,你也不认识我。但先制作网站后付款的网站建设流程,更有嘉禾免费网站建设让你可以放心的选择与我们合作。
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 v\G
*************************** 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?如果还想学到更多技能或想了解更多相关内容,欢迎关注创新互联行业资讯频道,感谢各位的阅读!