Gin Interface

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Opclass interface pseudocode. An example for a Gin opclass can be found in

ginarayproc.c.

Datum* extractValue(Datum inputValue, uint32* nentries)

Returns an array of Datum of entries of the value to be indexed. nentries

should contain the number of returned entries.

int compareEntry(Datum a, Datum b)

Compares two entries (not the indexing values)

Datum* extractQuery(Datum query, uint32* nentries, StrategyNumber n)

Returns an array of Datum of entries of the query to be executed.

n contains the strategy number of the operation.

bool consistent(bool[] check, StrategyNumber n, Datum query)

The size of the check array is the same as sizeof of the array returned by

extractQuery. Each element of the check array is true if the indexed value

has a corresponding entry in the query. i.e. if (check[i] == TRUE) then

the i-th entry of the query is present in the indexed value. The Function

should return true if the indexed value matches by StrategyNumber and

the query.