Returns the number of rows returned by the query.
Syntax
Restrictions
The following restrictions apply when you use the COUNT
function in the SELECT
command:
The expression must be a column, a numeric constant, or a string constant.
The function does not support the DISTINCT
or ALL
keywords.
The function does not support the OVER
clause.
The function always counts all rows for the query, including duplicates and nulls.
Examples
This example returns the number of incidents for which flood_controlled
is 0
(zero):
select count(*) from incident where flood_controlled = 0;
This example returns the number of problems for which problem_key
includes ORA-600
:
select count(*) from problem where problem_key like '%ORA-600%';