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id INT NOT NULL PRIMARY KEY AUTO_INCREMENT
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ALTER TABLE tablename DROP id;
ALTER TABLE tablename ADD id INT NOT NULL PRIMARY KEY AUTO_INCREMENT FIRST
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SQL code:
mysql> create table t_spf19871001(id INT NOT NULL PRIMARY KEY AUTO_INCREMENT,col
1 int);
Query OK, 0 rows affected (0.08 sec)
mysql> insert into t_spf19871001(col1) values (10),(20),(30),(40),(50),(60),(70),(80),(90);
Query OK, 9 rows affected (0.05 sec)
Records: 9 Duplicates: 0 Warnings: 0
mysql> select * from t_spf19871001;
+----+------+
| id | col1 |
+----+------+
| 1 | 10 |
| 2 | 20 |
| 3 | 30 |
| 4 | 40 |
| 5 | 50 |
| 6 | 60 |
| 7 | 70 |
| 8 | 80 |
| 9 | 90 |
+----+------+
9 rows in set (0.00 sec)
mysql> delete from t_spf19871001 where id in (1,4,7,8);
Query OK, 4 rows affected (0.05 sec)
mysql> select * from t_spf19871001;
+----+------+
| id | col1 |
+----+------+
| 2 | 20 |
| 3 | 30 |
| 5 | 50 |
| 6 | 60 |
| 9 | 90 |
+----+------+
5 rows in set (0.00 sec)
mysql> ALTER TABLE t_spf19871001 DROP id;
Query OK, 5 rows affected (0.13 sec)
Records: 5 Duplicates: 0 Warnings: 0
mysql> A
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