Subject: Re: Improve new hash partition bound check error messages
From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
To: Heikki Linnakangas <hlinnaka@iki.fi>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
References: <bb9d60b4-aadb-607a-1a9d-fdc3434dddcd@enterprisedb.com>
 <9fc7eb48-0e8f-0836-8def-bc4b242e9c63@iki.fi>
 <aeb41d57-da42-b46d-bfc1-4933afbc5658@enterprisedb.com>
 <b7a09729-7815-4bf5-c74c-211ac4997688@enterprisedb.com>
Message-ID: <0e685d51-d214-3dde-8e78-23edfec055dc@enterprisedb.com>
Date: Mon, 22 Feb 2021 08:09:46 +0100
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On 15.02.21 17:45, Peter Eisentraut wrote:
> On 2021-02-03 15:52, Peter Eisentraut wrote:
>> On 2021-02-02 13:26, Heikki Linnakangas wrote:
>>> How about this?
>>>
>>> CREATE TABLE fail_part PARTITION OF hash_parted FOR VALUES WITH (MODULUS
>>> 25, REMAINDER 3);
>>> ERROR:  every hash partition modulus must be a factor of the next larger
>>> modulus
>>> DETAIL:  25 is not divisible by 10, the modulus of existing partition
>>> "hpart_1"
>>
>> I don't know if we can easily get the name of the existing partition.
>> I'll have to check that.
>>
>> I'm worried that this phrasing requires the user to understand that
>> "divisible by" is related to "factor of", which is of course correct but
>> introduces yet more complexity into this.
>>
>> I'll play around with this a bit more.
> 
> Here is a new patch that implements the suggestions.

committed