ASA SQL Reference
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COUNT function [Aggregate]

Function 

Counts the number of rows in a group depending on the specified parameters.

Syntax 

COUNT (
*
| expression
|  DISTINCT { expression | column-name } )

Parameters 

*    Returns the number of rows in each group.

expression    Returns the number of rows in each group where the expression is not the null value.

DISTINCT expression or column-name    Returns the number of different values in the expression, or the column with name column-name. Rows where the value is the NULL value are not included in the count.

Standards and compatibility 

• SQL/92    SQL/92 compatible.

• SQL/99    Vendor extension.

• Sybase    Compatible with Adaptive Server Enterprise.

See also 

AVG function [Aggregate]

SUM function [Aggregate]

Example 

The following statement returns each unique city, and the number of rows with that city value:

SELECT city , Count(*)
FROM employee
GROUP BY city