MySQL 我能找出下一个auto_increment使用的值吗？

是的，你可以通过以下语法使用SELECT AUTO_INCREMENT找出下一个auto_increment的值 –

SELECT AUTO_INCREMENT
FROM INFORMATION_SCHEMA.TABLES 
WHERE TABLE_SCHEMA= yourDatabaseName AND TABLE_NAME=yourTableName;

让我们首先创建一个表 –

mysql> create table DemoTable
(
   ClientId int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   ClientName varchar(20),
   ClientAge int
);
Query OK, 0 rows affected (1.33 sec)

使用insert命令在表中插入一些记录 –

mysql> insert into DemoTable(ClientName,ClientAge) values('John',23);
Query OK, 1 row affected (0.35 sec)
mysql> insert into DemoTable(ClientName,ClientAge) values('Carol',21);
Query OK, 1 row affected (0.28 sec)
mysql> insert into DemoTable(ClientName,ClientAge) values('Bob',24);
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable(ClientName,ClientAge) values('David',25);
Query OK, 1 row affected (0.25 sec)

以下是使用select语句显示表中所有记录的查询 –

mysql> select *from DemoTable;

这将产生以下输出 –

+----------+------------+-----------+
| ClientId | ClientName | ClientAge |
+----------+------------+-----------+
| 1        | John       | 23        |
| 2        | Carol      | 21        |
| 3        | Bob        | 24        |
| 4        | David      | 25        |
+----------+------------+-----------+
4 rows in set (0.00 sec)

以下是在上述表中查找下一个auto_increment值的查询。

mysql> SELECT AUTO_INCREMENT 
FROM INFORMATION_SCHEMA.TABLES 
WHERE TABLE_SCHEMA= 'sample' AND TABLE_NAME='DemoTable';

这将产生以下输出 –

+----------------+
| AUTO_INCREMENT |
+----------------+
| 5              |
+----------------+
1 row in set (0.20 sec)

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