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Negator Functions

A negator function takes the same arguments as its companion function, in the same order, but returns the Boolean complement. That is, if a function returns TRUE for a given set of arguments, its negator function returns FALSE when passed the same arguments, in the same order. In certain cases, the database server can process a query more efficiently if the sense of the query is reversed. That is, "Is x greater than y?" changes to "Is y less than or equal to x?"

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