Count
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Another arithmetic 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) |
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) |