SQL EXISTS Operator - W3Schools

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The SQL EXISTS Operator

The EXISTS operator is used in a WHERE clause to check whether a subquery returns any rows.

The EXISTS operator evaluates to TRUE if the subquery returns at least one row, and FALSE otherwise.

EXISTS Syntax

SELECT column_name(s) FROM table_name WHERE EXISTS (subquery);

Demo Database

Below is a selection from the "Products" table in the Northwind sample database:

ProductID ProductName SupplierID CategoryID Unit Price
1 Chais 1 1 10 boxes x 20 bags 18.00
2 Chang 1 1 24 - 12 oz bottles 19.00
3 Aniseed Syrup 1 2 12 - 550 ml bottles 10.00
4 Chef Anton's Cajun Seasoning 2 2 48 - 6 oz jars 22.00
5 Chef Anton's Gumbo Mix 2 2 36 boxes 21.35

And a selection from the "Suppliers" table:

SupplierID SupplierName ContactName Address City PostalCode Country
1 Exotic Liquid Charlotte Cooper 49 Gilbert St. London EC1 4SD UK
2 New Orleans Cajun Delights Shelley Burke P.O. Box 78934 New Orleans 70117 USA
3 Grandma Kelly's Homestead Regina Murphy 707 Oxford Rd. Ann Arbor 48104 USA
4 Tokyo Traders Yoshi Nagase 9-8 Sekimai Musashino-shi Tokyo 100 Japan

SQL EXISTS Examples

The following SQL checks if any suppliers has a product with a price lower than 10. If the subquery evaluates to TRUE; list the suppliers with a product price less than 10:

Example

SELECT SupplierNameFROM SuppliersWHERE EXISTS ( SELECT ProductName FROM Products WHERE Products.SupplierID = Suppliers.supplierID AND Price < 10); Try it Yourself »

The following SQL checks if any suppliers has a product with a price equal to 22. If the subquery evaluates to TRUE; list the suppliers with a product price equal to 22:

Example

SELECT SupplierNameFROM SuppliersWHERE EXISTS ( SELECT ProductName FROM Products WHERE Products.SupplierID = Suppliers.supplierID AND Price = 22); Try it Yourself » ❮ Previous Next ❯ ★ +1 Sign in to track progress

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