On 5/10/16 9:16 PM, David G. Johnston wrote:
> Brute force: you'd have to query pg_amop and note the absence of a row
> with a btree (maybe hash too...) family strategy 3 (1 for hash)
> [equality] where the left and right types are the same and match the
> type in question.
While these are good thoughts, the implementation of DISTINCT actually
looks for an operator that is literally named "=".
--
Peter Eisentraut http://www.2ndQuadrant.com/
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