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- 4D - SQL Reference
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- Syntax rules
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Syntax rules
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4d_function_call
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4d_language_reference
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all_or_any_predicate
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arithmetic_expression
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between_predicate
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case_expression
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column_definition
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column_reference
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command_parameter
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comparison_predicate
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exists_predicate
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foreign_key_definition
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function_call
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in_predicate
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is_null_predicate
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like_predicate
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literal
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predicate
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primary_key_definition
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search_condition
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select_item
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sort_list
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sql_data_type_name
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sql_name
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sql_string
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subquery
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table_constraint
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table_reference
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4D v20 R7
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')
Siehe auch
EIGENSCHAFTEN
Produkt: 4D
Thema: Syntax rules
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4D - SQL Reference ( 4D v20 R7)
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