In particular it is not necessary to check <structfield>sk_flags</> to

see if the comparison value is NULL, because the SP-GiST core code

will filter out such conditions.

The array <structfield>orderbykeys>, of length <structfield>norderbys</>,

The array <structfield>orderbykeys</>, of length <structfield>norderbys</>,

describes the ordering operators in the same fashion.

<structfield>reconstructedValue</> is the value reconstructed for the

parent tuple; it is <literal>(Datum) 0</> at the root level or if the