COUNT_BIG (Transact-SQL)
Returns the number of items in a group. COUNT_BIG works like the COUNT function. The only difference between the two functions is their return values. COUNT_BIG always returns a bigint data type value. COUNT always returns an int data type value. May be followed by the OVER Clause (Transact-SQL).
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. 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 getting rid of duplicates. It counts each row separately. This includes rows that contain null values.
Return Types
bigint
Remarks
COUNT_BIG(*) returns the number of items in a group. This includes 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.