SQL Server Constraints Explained: PK, FK, UNIQUE, CHECK & More
A complete walkthrough of SQL Server's constraint types — your database's built-in guard rails for enforcing data integrity.
Covered in this video:
0:00 Intro
0:16 Overview of constraint types
0:22 PRIMARY KEY
0:42 FOREIGN KEY
1:04 UNIQUE
1:19 NOT NULL
1:31 DEFAULT
1:44 CHECK
1:59 Disabling & re-enabling constraints (NOCHECK vs WITH CHECK)
2:11 Summary
Whether you're designing a new schema or auditing an existing one, understanding how these constraints work — and how to safely disable/re-enable them — is essential for keeping your data consistent and your queries fast.
#SQLServer #SQL #Database #DataIntegrity #TSQL