mysql 左联结与右联结
mysql>select*fromtest;+----+------------+-------+-----------+|id|name|score|subject|+----+------------+-------+-----------+|1|xiaoming|89|shuxue||2|xia...
mysql 表联结，内部联结
mysql>select*fromuser;+------+----------+-----------+|id|name|address|+------+----------+-----------+|1|xiaoming|beijing||2|xiaobai|shandong||3|xiaohon...
mysql 创建联结
mysql>select*fromuser;+------+----------+-----------+|id|name|address|+------+----------+-----------+|1|xiaoming|beijing||2|xiaobai|shandong||3|xiaohon...