STRICT functions return NULL if any of their inputs are NULL according
to the manual, so that they need not be executed at all.
Unless it is a Set Returning Function, in which case a NULL input is
not reduced nor does it to appear to be handled as a special case in
the executor function scan code.
So a function that is both STRICT and SET RETURNING will return rows.
Presumably this is just a case of missing documentation?
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Simon Riggs http://www.2ndQuadrant.com/
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