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Rev

I like this solution because it's very concise. Any thoughts about the performance of the solution that I posted below? stackoverflow.com/a/46775289/968244

isapir
– isapir

2017-10-16 17:04:18 +00:00
Commented Oct 16, 2017 at 17:04
I was actually able to test it. I have a table with about 350k rows and it had 39 duplicates over 7 columns with no indices. I tried the GROUP BY solution first and it was taking over 30 seconds so I killed it. I then tried the USING solution and it completed in about 16 seconds.

isapir
– isapir

2017-10-16 17:15:16 +00:00
Commented Oct 16, 2017 at 17:15
1

@isapir: Like I mentioned back in 2014: NOT IN is conveniently short syntax, but EXISTS is faster. (Same as your completely valid query with the USING clause.) But there is a subtle difference. I added a note above.

Erwin Brandstetter
– Erwin Brandstetter

2017-10-17 04:01:52 +00:00
Commented Oct 17, 2017 at 4:01

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