MySQL count() Function

The MySQL count() function is used to return the count of an expression. It is used when you need to count some records of your table.

Syntax:

snippet
SELECT COUNT (aggregate_expression)
FROM table_name
[WHERE conditions];

Parameter explanation

aggregate_expression: It specifies the column or expression whose NON-NULL values will be counted.

table_name: It specifies the tables, from where you want to retrieve records. There must be at least one table listed in the FROM clause.

WHERE conditions: It is optional. It specifies the conditions that must be fulfilled for the records to be selected.

MySQL count() function example

Consider a table named "officers", having the following data.

mysql count() 1

Execute the following query:

snippet
SELECT COUNT(officer_name)
FROM officers;

Output:

mysql count() 2

Here, you can see that that the COUNT function calculates the total number of officers in the table.

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