mysql 创建联结

mysql> select * from user;
+------+----------+-----------+
| id   | name     | address   |
+------+----------+-----------+
|     | xiaoming | beijing   |
|     | xiaobai  | shandong  |
|     | xiaohong | suzhou    |
|     | xiaohei  | changchun |
+------+----------+-----------+
 rows in set (0.00 sec)

mysql> select * from test;
+----+------------+-------+-----------+
| id | name       | score | subject   |
+----+------------+-------+-----------+
|   | xiaoming   |     | shuxue    |
|   | xiaohong   |     | shuxue    |
|   | xiaohong   |     | english   |
|   | xiaohong   |     | physics   |
|   | xiaohong   |     | astronaut |
|   | xiaoming   |     | physics   |
|   | xiaoming   |     | astronaut |
|   | xiaoming   |     | english   |
|   | xiaobai    |     | astronaut |
|  | .2xiaobai |     | english   |
|  | .2xiaobai |     | physics   |
|  | 3xiaobai   |     | shuxue    |
|  | 123xiaohei |     | astronaut |
|  | xiaohei    |     | shuxue    |
|  | xiaohei    |     | physics   |
|  | .12xiaohei |     | english   |
+----+------------+-------+-----------+
 rows in set (0.00 sec)

mysql> select test.name,score,subject,address from test,user where user.name=test.name;
+----------+-------+-----------+-----------+
| name     | score | subject   | address   |
+----------+-------+-----------+-----------+
| xiaoming |     | shuxue    | beijing   |
| xiaohong |     | shuxue    | suzhou    |
| xiaohong |     | english   | suzhou    |
| xiaohong |     | physics   | suzhou    |
| xiaohong |     | astronaut | suzhou    |
| xiaoming |     | physics   | beijing   |
| xiaoming |     | astronaut | beijing   |
| xiaoming |     | english   | beijing   |
| xiaobai  |     | astronaut | shandong  |
| xiaohei  |     | shuxue    | changchun |
| xiaohei  |     | physics   | changchun |
+----------+-------+-----------+-----------+
 rows in set (0.01 sec)