mysql 如何对大表进行连接操作
有两个表
weibo 数据行765W-766W
+---------+---------------+------+-----+-------------------+-----------------------------+
| Field | Type | Null | Key | Default | Extra |
+---------+---------------+------+-----+-------------------+-----------------------------+
| wid | varchar(20) | YES | | NULL | |
| uid | varchar(20) | YES | | NULL | |
| cn | int(11) | YES | | NULL | |
| rt | int(11) | YES | | NULL | |
| tem | timestamp | NO | | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
| content | varchar(2000) | YES | | NULL | |
+---------+---------------+------+-----+-------------------+-----------------------------+
userprofile 数据行98w-99w
+----------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+----------+-------------+------+-----+---------+-------+
| uid | varchar(20) | YES | | NULL | |
| username | varchar(30) | YES | | NULL | |
+----------+-------------+------+-----+---------+-------+
老师要求是对这两个表进行连接join操作 通过uid连接wid 和 username
在本机上运行 许久没有结果,
同时 对两个表设置主键(创建表的时候忘记了)和索引都许久没有结果。
求指点。