PostgreSQL COUNT Function
COUNT
The COUNT()
function returns the number of rows that matches a specified criterion.
If the specified criterion is a column name,
the COUNT() function returns the number of columns with that name.
Example
Return the number of customers from the customers table:
SELECT COUNT(customer_id)
FROM customers;
Run Example »
Note: NULL values are not counted.
By specifying a WHERE clause, you can e.g. return the number of customers
that comes from London:
Example
Return the number of customers from London:
SELECT COUNT(customer_id)
FROM customers
WHERE city = 'London';
Run Example »
Exercise?What is this?
Test your skills by answering a few questions about the topics of this page
True or False.
The COUNT function does not work on String values.
