COUNT() Function

COUNT() Function

The COUNT() function returns the number of rows that matches a specified criteria.

SQL COUNT(column_name) Syntax

The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column:
SELECT COUNT(column_name) FROM table_name;

SQL COUNT(*) Syntax

The COUNT(*) function returns the number of records in a table:
SELECT COUNT(*) FROM table_name;
The COUNT(DISTINCT column_name) function returns the number of distinct values of the specified column:

SQL COUNT(DISTINCT column_name) Syntax

SELECT COUNT(DISTINCT column_name) FROM table_name;
Note: COUNT(DISTINCT) works with ORACLE and Microsoft SQL Server, but not with Microsoft Access.
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COUNT-Function aggregate-functions NULL-values

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