CaseExpression.Case abbreviation COALESCE

Returns the first operand that is not equal to NULL. If all operands are NULL then returns NULL

Format

COALESCE( Operand1, Operand2 [, Operand]* )

Remarks

This is a shorthand form of the CASE statement.

The expression:

COALESCE(x,y)

is equivalent to:

CASE WHEN x IS NOT NULL THEN x ELSE y END

The return value is the first nonnull operand or NULL if all operands are equal to NULL.

Operand1, Operand2 and Operandcan be any expression.