Null (SQL)
SPECIAL MARKER AND KEYWORD IN SQL INDICATING THAT SOMETHING HAS NO VALUE
Sql null; NULL (SQL); NVL; NULLIF; SQL CASE; Sql case; Codd tables; Codd table; COALESCE; C-table; Uncertain database; NULL marks; Null (database)
In SQL, null or NULL is a special marker used to indicate that a data value does not exist in the database. Introduced by the creator of the relational database model, E.