Creating tables in SQL Server

Alter table table1 add constraint <name of constraint>
FOREIGN KEY (<column>) references table2 (<primary key column>)

Foreign constraint prevents invalid data from being entered into the foreign key column. The foreign key value must be one of the values contained in the table it references.

Creating a table using sql

Create Table tblGender { ID int NOT NULL Primary Key, Gender nvarchar(50) NOT NULL,

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