请教一下,MySQL建立视图联合显示多表数据,索引是怎么使用的? 如题,视图支持索引吗?如果不支持索引那可得不偿失了。 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 以查询SELECT语句的索引使用方法相同。没有差别。你可以explain 一下看看。mysql> create view v_t1 as select * from t1 where id<100;Query OK, 0 rows affected (0.56 sec)mysql> explain select * from t1 where id<100;+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+| id | select_type | table | type | possible_keys | key | key_len | ref |rows | Extra |+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+| 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL | 98 | Using where |+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+1 row in set (0.05 sec)mysql> explain select * from v_t1;+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+| id | select_type | table | type | possible_keys | key | key_len | ref |rows | Extra |+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+| 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL | 98 | Using where |+----+-------------+-------+-------+---------------+---------+---------+------+------+-------------+1 row in set (0.00 sec)mysql> mysql 的视图是没有索引的,除非是merge算法的视图,merge算法的视图一句话讲不清楚,基本可以理解mysql的视图用不到基本表的索引。 mysql 表类型问题 存储过程时间函数出错 mysql命令行下输入什么命令可以弹出一个一个文档编辑框 在一个数据库中用update语句更新另一个库里的表的问题 关于MYSQL的瓶颈问题 向大侠请教,在mysql中装载数据? postgres select now();问题 商城的订单表应该用myisam好还是innodb好? 将json解析并导入数据库中 mysql如何每次查10条数据直到查完 如何知道mysql分区时对应的哪个字段呢? 关于截取BLOB类型数据
mysql> create view v_t1 as select * from t1 where id<100;
Query OK, 0 rows affected (0.56 sec)mysql> explain select * from t1 where id<100;
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
| id | select_type | table | type | possible_keys | key | key_len | ref |
rows | Extra |
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
| 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL |
98 | Using where |
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
1 row in set (0.05 sec)mysql> explain select * from v_t1;
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
| id | select_type | table | type | possible_keys | key | key_len | ref |
rows | Extra |
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
| 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL |
98 | Using where |
+----+-------------+-------+-------+---------------+---------+---------+------+-
-----+-------------+
1 row in set (0.00 sec)mysql>