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Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On 4/11/18 17:38, Peter Geoghegan wrote: > On Wed, Apr 11, 2018 at 2:29 PM, Peter Eisentraut > wrote: >> But in this case it doesn't even do equality comparison, it just returns >> the value. > > That's the idea that I tried to express. The point is that we need to > tell the user that there is no need to worry about it, rather than > that they're wrong to ask about it. Though we should probably actually > just throw an error. Or maybe it should be the collation of the underlying table columns. Otherwise the collation returned by an index-only scan would be different from a table scan, no? -- Peter Eisentraut http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services