SQL EXISTS Operator

SQL

SQL EXISTS Operator : SQL EXISTS Operator is used to test for the existence of any record in a subquery.

  • The EXISTS operator returns true if the subquery returns one or more records.

EXISTS Syntax

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

 

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
2 Chang 1 1 24 – 12 oz bottles 19
3 Aniseed Syrup 1 2 12 – 550 ml bottles 10
4 Chef Anton’s Cajun Seasoning 2 2 48 – 6 oz jars 22
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 statement returns TRUE and lists the suppliers with a product price less than 20:

Example

SELECT SupplierName
FROM Suppliers
WHERE EXISTS (SELECT ProductName FROM Products WHERE SupplierId = Suppliers.supplierId AND Price < 20);

 

Output

Number of Records: 24

SupplierName
Exotic Liquid
New Orleans Cajun Delights
Tokyo Traders
Mayumi’s
Pavlova, Ltd.
Specialty Biscuits, Ltd.
PB Knäckebröd AB
Refrescos Americanas LTDA
Heli Süßwaren GmbH & Co. KG
Plutzer Lebensmittelgroßmärkte AG
Formaggi Fortini s.r.l.
Norske Meierier
Bigfoot Breweries
Svensk Sjöföda AB
Aux joyeux ecclésiastiques
New England Seafood Cannery
Leka Trading
Lyngbysild
Zaanse Snoepfabriek
Karkki Oy
G’day, Mate
Ma Maison
Pasta Buttini s.r.l.
Escargots Nouveaux

 

The following SQL statement returns TRUE and lists the suppliers with a product price equal to 22:

Example

SELECT SupplierName
FROM Suppliers
WHERE EXISTS (SELECT ProductName FROM Products WHERE SupplierId = Suppliers.supplierId AND Price = 22);

 

Output

Number of Records: 1

SupplierName
New Orleans Cajun Delights