Why is it not sane to pass ExecStoreTuple(shouldFree=true) for tuples point into buffers

Hi,

I've the need to persist a the result of an index_getnext() in a tuple
slot. I don't want to unneccessarily duplicate the tuple data itself, so
I'd like to use ExecStoreTuple(buffer = real_buffer) notion. But since
the next index_getnext()/index_endscan() will overwrite/release the
heaptuple I need to copy the HeapTupleData().
It'd be rather useful to be able to do ExecStoreTuple(tuple, slot,
some_buffer, true), i.e. hav ethe HeapTupleData struct freed *and* the
buffer pinned. There's an Assert preventing that though.

Why?

Greetings,

Andres Freund

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Andres Freund http://www.2ndQuadrant.com/
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