| From: | Victor Yegorov <vyegorov(at)gmail(dot)com> |
|---|---|
| To: | Thomas Kellerer <spam_eater(at)gmx(dot)net> |
| Cc: | "pgsql-general(at)postgresql(dot)org" <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: bpchar, text and indexes |
| Date: | 2016-02-22 16:09:50 |
| Message-ID: | CAGnEboikS7=hq64BmTrJqRBLx9R1CzWv6EY2RfppSoo9iHgOUQ@mail.gmail.com |
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| Lists: | pgsql-general |
2016-02-22 18:00 GMT+02:00 Thomas Kellerer <spam_eater(at)gmx(dot)net>:
> I assume that this has to do with the fact that char(n) is blank padded to
> 20 character.
>
Yes, this was my thought too, but I do not understand what is going on in
details.
To be able to correctly compare that to a text value, sn_c has to be casted
> to text and then the index (which contains blank padded values) can not be
> used any more.
>
Well, for `varchar` type Postgres is able to do `varchar` -> `bpchar` cast
for my constant. I do not understand why for `text` it cannot and casts
column instead.
--
Victor Y. Yegorov
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