将主键更改为复合键(主键已存在) [英] Change Primary Key to Composite Key (Primary Key already exists)

问题描述

我正在尝试将我的 SQL 数据库中表的主键从现有键更改为复合键，其中不包括现有列.由于以下错误消息，以下代码不起作用:

I am trying to change the primary key of a table in my SQL database from the existing key to a composite key, which does not include the existing column. The following code is not working due to the following error messages:

删除主键:

PRIMARY 附近的语法不正确.期待 COLUMN、CONSTRAINT、ID 或QUOTED_ID

Incorrect Syntax near PRIMARY. Expecting COLUMN, CONSTRAINT, ID, or QUOTED_ID

添加主键:

PRIMARY 附近的语法不正确.期待 ID

T-SQL 代码:

ALTER TABLE AgentIdentification 
DROP PRIMARY KEY Number, 
ADD PRIMARY KEY (AgentId, IdIndicator)

编辑

我可以通过使用以下两个查询语句来完成此操作

I was able to accomplish this by using the following two query statements

ALTER TABLE AgentIdentification 
DROP CONSTRAINT [PK_AgentId_Id]
GO

ALTER TABLE AgentIdentification
ADD CONSTRAINT pk_PersonID PRIMARY KEY (AgentId, IdIndicator)

我不需要请求 SQLDROP PRIMARY KEY"，而是告诉它DROP CONSTRAINT"，将这两个操作分成两个查询也有帮助.

Instead of requesting that SQL "DROP PRIMARY KEY" I needed to tell it to "DROP CONSTRAINT", also separating these two actions into two queries helped.

推荐答案

    /* For SQL Server/Oracle/MS ACCESS */
    ALTER TABLE  AgentIdentification 
    DROP CONSTRAINT PK_Table1_Col1


    /* For MySql */
    ALTER TABLE  AgentIdentification 
    DROP PRIMARY KEY

添加主键:

MySQL / SQL Server / Oracle / MS Access:

ALTER TABLE Table1
ADD CONSTRAINT pk_PersonID PRIMARY KEY (AgentId, IdIndicator)

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