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spørsmålet		svaret
Ensures that a column cannot have a NULL value begynn å lære		NOT NULL
Ensures that all values in a column are different begynn å lære		UNIQUE
A combination of a NOT NULL and UNIQUE. Uniquely identifies each row in a table begynn å lære		PRIMARY KEY [MySQL:] UserId auto_increment primary key
Uniquely identifies a row/record in another table begynn å lære		FOREIGN KEY
Ensures that all values in a column satisfies a specific condition begynn å lære		CHECK
Sets a default value for a column when no value is specified begynn å lære		DEFAULT
Used to create and retrieve data from the database very quickly begynn å lære		INDEX
It's like a declaration of default value that increments by 1 for each record. begynn å lære		auto_increment SQLite: autoincrement

SQL – Constraints