Re: enum types and binary queries

Поиск
Список
Период
Сортировка
От Andrew Dunstan
Тема Re: enum types and binary queries
Дата
Msg-id 46D710E2.3070604@dunslane.net
обсуждение исходный текст
Ответ на enum types and binary queries  ("Merlin Moncure" <mmoncure@gmail.com>)
Ответы Re: enum types and binary queries
Список pgsql-hackers

Merlin Moncure wrote:
> I noticed that enums are not available to be queried as binary through
> the protocol.  Is this a known issue?  Too late to fix for 8.3?  This
> is kind of a pain, because it forces any query that returns an enum to
> return the entire result as text.  afaik, enums are the only POD type
> to behave this way.
>
> postgres=# create type foo as enum('foo');
> CREATE TYPE
>
> postgres=# copy (select 'foo'::foo) to '/home/postgres/foo.txt' binary;
> ERROR:  no binary output function available for type foo
>   


The trouble is that an enum doesn't have an immutable internal binary value.

I guess we could say that the binary value is the integer offset of the 
value in the enum ordering, and translate it back on input. Providing 
the binary IO funcs shouldn't be too hard if we do that, unless I'm 
missing something.

cheers

andrew




В списке pgsql-hackers по дате отправления:

Предыдущее
От: Tom Lane
Дата:
Сообщение: Re: Advice on MyXactMade* flags, MyLastRecPtr, pendingDeletes and lazy XID assignment
Следующее
От: Tom Lane
Дата:
Сообщение: Re: [ADMIN] reindexdb hangs