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SQL自学，mysql从入门到精通 --- 第 7 天，表的联合

news 2025/2/10 20:44:43

表的联合

在一个SELECT 语句中使用多个表

-- 将table1和table2的每一行都接合了起来
root@mysqldb 15:22:  [d1]> SELECT * FROM project, project2;
+------+---------------------+---------------------+------+------------+------------+
| task | StartTime           | endtime             | task | StartTime  | endtime    |
+------+---------------------+---------------------+------+------------+------------+
| AA   | 2023-07-15 10:00:00 | 2023-08-01 00:00:00 | AA   | 2023-07-15 | 2023-08-01 |
| BB   | 2023-07-20 10:00:00 | 2023-08-02 10:00:00 | AA   | 2023-07-15 | 2023-08-01 |
| CC   | 2023-08-16 00:00:00 | 2023-08-25 00:00:00 | AA   | 2023-07-15 | 2023-08-01 |
| DD   | 2023-09-02 00:00:00 | 2023-09-06 00:00:00 | AA   | 2023-07-15 | 2023-08-01 |
| EE   | 2023-09-01 10:00:00 | 2023-09-05 00:00:00 | AA   | 2023-07-15 | 2023-08-01 |
| AA   | 2023-07-15 10:00:00 | 2023-08-01 00:00:00 | BB   | 2023-07-20 | 2023-08-02 |
| BB   | 2023-07-20 10:00:00 | 2023-08-02 10:00:00 | BB   | 2023-07-20 | 2023-08-02 |
| CC   | 2023-08-16 00:00:00 | 2023-08-25 00:00:00 | BB   | 2023-07-20 | 2023-08-02 |
| DD   | 2023-09-02 00:00:00