COUNT ( { [ DISTINCT | ALL ] value_expression | * } )
Syntax Elements
- DISTINCT
- Exclude duplicates specified by value_expression from the computation.
- The expression cannot contain any ordered analytical or aggregate functions.
- ALL
- All values of value_expression that are not null, including duplicates, are included in the computation.
- value_expression
- A literal or column expression for which the number of values is to be counted.
- The value_expression cannot be a reference to a view column derived from a function, and cannot contain any ordered analytical or aggregate functions.
- *
- Counts all rows in the group of rows on which COUNT operates.