4D v13.4

exists_predicate

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4D v13.4
exists_predicate

exists_predicate  


 

 

EXISTS (subquery)

An exists_predicate is used to indicate a subquery and then check whether it returns anything. This is done by passing the EXISTS keyword followed by the subquery.

Example  

This example returns the total sales when there is a store in the region specified:

SELECT SUM (Sales)
FROM Store_Information
WHERE EXISTS
(SELECT * FROM Geography
WHERE region_name = 'West')

 
PROPERTIES 

Product: 4D
Theme: Syntax rules

 
INDEX

Alphabetical list of commands

 
SEE ALSO 

predicate
subquery