Release 10.1A: OpenEdge Data Management:
SQL Reference

COUNT

Computes either the number of rows in a group of rows or the number of non-NULL values in a group of values.

Syntax

COUNT ( { [ ALL ] expression } | { DISTINCT column_ref } | * )

Example

This example illustrates the COUNT function:

SELECT COUNT (*) FROM orders WHERE order_date = SYSDATE ;

Notes

The keyword DISTINCT specifies that the duplicate values are to be eliminated before computing the count.
If the argument to COUNT function is ‘*’, then the function computes the count of the number of rows in a group.
If the argument to COUNT function is not ‘*’, then NULL values are eliminated before the number of rows is computed.
The argument column_ref or expression can be of any type.
The result of the function is of integer type. The result is never NULL.