COUNT_BIG
Returns the number of items in a group. COUNT_BIG works like the COUNT function. The only difference between them is their return values: COUNT_BIG always returns a bigint data type value. COUNT always returns an int data type value.
Syntax
COUNT_BIG ( { [ ALL | DISTINCT ] expression } | * )
Arguments
ALL
Applies the aggregate function to all values. ALL is the default.
DISTINCT
Specifies that COUNT_BIG returns the number of unique nonnull values.
expression
Is an expression of any type except uniqueidentifier, text, image, or ntext. Aggregate functions and subqueries are not permitted.
*
Specifies that all rows should be counted to return the total number of rows in a table. COUNT_BIG(*) takes no parameters and cannot be used with DISTINCT. COUNT_BIG(*) does not require an expression parameter because, by definition, it does not use information about any particular column. COUNT_BIG(*) returns the number of rows in a specified table without eliminating duplicates. It counts each row separately, including rows that contain null values.
Return Types
bigint
Remarks
COUNT_BIG(*) returns the number of items in a group, including NULL values and duplicates.
COUNT_BIG(ALL expression) evaluates expression for each row in a group and returns the number of nonnull values.
COUNT_BIG(DISTINCT expression) evaluates expression for each row in a group and returns the number of unique, nonnull values.