When you use IN, you’re telling SQL to take a value and compare it against every value or set of values in a list using =. If any NULL values exist, a row will not be returned–even if both ...

When a variable is specified as NOT NULL, you must initialize the variable when it is declared. For example: The below example declares two variables, one of which is a not null. DECLARE salary number ...

IS NULL and IS MISSING are predicates that test for a missing value. IS NULL and IS MISSING are used in the WHERE, ON, and HAVING expressions. Each predicate resolves to true if the sql-expression's ...