Data Type

A rule defining which values a column or expression may contain and which operations apply.

What is Data Type in a relational database?

Data Type — A rule defining which values a column or expression may contain and which operations apply.

CREATE TABLE customer (
    customer_id INTEGER PRIMARY KEY,
    email CHARACTER VARYING(255) NOT NULL,
    status CHARACTER VARYING(20) DEFAULT 'active'
);

Level: Novice · More Database terms at this level

Updated September 27, 2026