SQL Server creates table-related

Source: Internet
Author: User

1, three ways to set the primary key for SQL

A, field name int primary key

b, field name int constraint primary Key name primary key clustered (field name)

C, create the table is, after the sentence: Constraint primary Key name primary key clustered (field name)

A table can only create one primary key, one primary key can contain multiple columns, the primary key cannot be null and cannot be duplicated, and the primary key is automatically created as a clustered index.

SQL Server creates table-related

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