4D v12.1
exists_predicate
- 4D SQL Reference
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- Syntax rules
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- Syntax rules
- 4d_function_call
- 4d_language_reference
- all_or_any_predicate
- arithmetic_expression
- between_predicate
- case_expression
- column_definition
- column_reference
- command_parameter
- comparison_predicate
- exists_predicate
- foreign_key_definition
- function_call
- in_predicate
- is_null_predicate
- like_predicate
- literal
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- primary_key_definition
- search_condition
- select_item
- sort_list
- sql_data_type_name
- sql_name
- sql_string
- subquery
- table_constraint
- table_reference
4D v12.1
exists_predicate
exists_predicate
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EXISTS (subquery) |
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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.
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
SEE ALSO
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