WHERE clause

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March 16, 2025
+ 12
The WHERE clause filters resultsets based specified conditions.

Purpose

When you want to narrow down your resultset by one or more criteria, use the WHERE clause to filter your resultset.

Syntax

where-clause ::= 'WHERE' cond
Syntax diagram: refer to source code listing

Arguments

cond

[Required] Conditional expression that represents a filter to be applied to the resultset. Records for which the condition resolves to TRUE are propagated to the resultset.

You can construct complex conditional expressions, for example by using the logical operators AND, OR, and NOT.

Examples

To try the examples in this section, set the query context to the inventory scope in the travel sample dataset. For more information, see Query Context.

Example 1. Use WHERE filter the resultset

To list only airports that are in France, use the WHERE clause for the "country" field.

sql++
SELECT airportname, city, country FROM airport WHERE country = "France" LIMIT 4;
Results
json
[ { "airportname": "Calais Dunkerque", "city": "Calais", "country": "France" }, { "airportname": "Peronne St Quentin", "city": "Peronne", "country": "France" }, { "airportname": "Les Loges", "city": "Nangis", "country": "France" }, { "airportname": "Couterne", "city": "Bagnole-de-l'orne", "country": "France" } ]
Example 2. Use WHERE and OR to filter the resultset

List only the landmarks that start with the letter "C" or "K". Note that the first position of the SUBSTR function is 0.

sql++
SELECT name FROM landmark WHERE CONTAINS(SUBSTR(name,0,1),"C") OR CONTAINS(SUBSTR(name,0,1),"K") LIMIT 4;
Results
json
[ { "name": "City Chambers" }, { "name": "Kingston Bridge" }, { "name": "Clyde Arc" }, { "name": "Clyde Auditorium" } ]
Example 3. Use WHERE, AND and NOT to filter the resultset

List landmark restaurants, except Thai restaurants.

sql++
SELECT name, activity FROM landmark WHERE activity = "eat" AND NOT CONTAINS(name,"Thai") LIMIT 4;
Results
json
[ { "activity": "eat", "name": "Hollywood Bowl" }, { "activity": "eat", "name": "Spice Court" }, { "activity": "eat", "name": "Beijing Inn" }, { "activity": "eat", "name": "Ossie's Fish and Chips" } ]