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SQL Server how to set the primary key self-growth, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain in detail for you, people with this need can come to learn, I hope you can gain something.

1. Create a new data table with the field id, and set id as the primary key to copy the code as follows: create table tb (id int,constraint pkid primary key (id)) create table tb (id int primary key)

two。 Create a new data table with the field id, set id as the primary key, and automatically number and copy the code as follows: create table tb (id int identity (1prime1), constraint pkid primary key (id)) create table tb (id int identity (1mem1) primary key)

3. We have built a data table with the field id, and set id as the primary key to copy the code as follows: alter table tb alter column id int not null alter table tb add constraint pkid primary key (id)

4. The copy code for deleting the primary key is as follows: Declare @ competitive varChar; Select @ Pk=Name from sysobjects where Parent_Obj=OBJECT_ID ('tb') and xtype='PK'; if @ competitive is not null exec (' Alter table tb Drop'+ @ competitive)

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