A predicate specifies a condition that is true, false, or unknown about a given row or group.
The following rules apply to all types of predicates:
Row-value expression: The operand of several
predicates (basic, quantified, and IN) can be a row-value-expression:
A row-value-expression returns a single row that consists of one or more column values. The values can be specified as a list of expressions. The number of columns that are returned by the row-value-expression is equal to the number of expressions that are specified in the list.
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