Sam Mason <sam(at)samason(dot)me(dot)uk> writes:
> I'm not sure what you're responding to here, but I'm pretty sure the OP
> wants IMMUTABLE and does not want STRICT/RETURNS NULL ON NULL INPUT.
Yeah --- STRICT will prevent inlining. The function's expression
actually is strict, but the planner isn't smart enough about NULLIF
to realize that, so it doesn't inline.
regards, tom lane