我们能在 MySQL 中使用 PRIMARY KEY(column1, column2) 来配对吗?
mysqlmysqli database更新于 2023/11/27 2:01:00
是的，您可以使用以下语法。以下是语法 −
PRIMARY KEY(yourColumnName1,yourColumnName2);
首先我们创建一个表 −
mysql> create table DemoTable -> ( -> StudentFirstName varchar(100), -> StudentLastName varchar(100), -> StudentAge int, -> StudentCountryName varchar(100), -> PRIMARY KEY(StudentFirstName,StudentLastName) -> ); Query OK, 0 rows affected (0.74 sec)
让我们检查一下表的描述 −
mysql> desc DemoTable;
输出
这将产生以下输出 −
+--------------------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +--------------------+--------------+------+-----+---------+-------+ | StudentFirstName | varchar(100) | NO | PRI | NULL | | | StudentLastName | varchar(100) | NO | PRI | NULL | | | StudentAge | int(11) | YES | | NULL | | | StudentCountryName | varchar(100) | YES | | NULL | | +--------------------+--------------+------+-----+---------+-------+ 4 rows in set (0.00 sec)
