如何在mysql中将自动编号插入字段ID？

Question

如何在MySQL中将自动编号插入字段ID？我有idmember这是主键已经 这是我曾尝试代码，请改正

UPDATE member SET id = Row_number()over ORDER BY idmember 

You have an error in your SQL syntax; check the manual that corresponds to your MySQL 
server version for the right syntax to use near 'over order by idmember' at line 1 

Answer 1

CREATE TABLE member (id INT PRIMARY KEY, idmember INT); 
INSERT INTO member (id, idmember) VALUES (10, 10), (11, 20), (12, 42); 

SELECT * FROM member; 
+----+----------+ 
| id | idmember | 
+----+----------+ 
| 10 |  10 | 
| 11 |  20 | 
| 12 |  42 | 
+----+----------+ 

SET @i := 0; 
UPDATE member SET id = @i:=@i+1 ORDER BY idmember; 

SELECT * FROM member; 
+----+----------+ 
| id | idmember | 
+----+----------+ 
| 1 |  10 | 
| 2 |  20 | 
| 3 |  42 | 
+----+----------+ 

Answer 2

设置你的ID字段从表结构AUTO_INCREMENT，那么它会增加自动