SQL Tutorial

Another arithematic function is COUNT. This allows us to COUNT up the number of row in a certain table. The syntax is,

SELECT COUNT("column_name")
FROM "table_name"

For example, if we want to find the number of store entries in our table,

Table Store_Information

store_name	Sales	Date
Los Angeles	$1500	Jan-05-1999
San Diego	$250	Jan-07-1999
Los Angeles	$300	Jan-08-1999
Boston	$700	Jan-08-1999

we'd key in

SELECT COUNT(store_name)
FROM Store_Information

Result:

Count(store_name)

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COUNT and DISTINCT can be used together in a statement to fetch the number of distinct entries in a table. For example, if we want to find out the number of distinct stores, we'd type,

SELECT COUNT(DISTINCT store_name)
FROM Store_Information

Result:

Count(DISTINCT store_name)

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