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Here are 3 interesting (to me) numbers: 1. creating index on _expression_ (func(timestamp)) takes 5 seconds 2. creating check constraint on the same _expression_ takes 10 seconds 3. adding partition table based on the same _expression_ without check _expression_ takes 20 seconds (this has been resolved by answer from David Rowley)
I tried various kind of indices to optimize 2. but nothing helps. When creating check constraint on column values directly is very fast (seems analyze helps), but creating check constraint on _expression_ is very slow, even twice as long as creating index on the same _expression_.
Is it possible to use indices to create check expressions? Why is 2. twice as long as 1.? Why is 3. twice as long as 2.? (when there is no appropriate check constraint for 3.)
Thank you, Dinko
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