From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
---|---|
To: | Tatsuo Ishii <ishii(at)sraoss(dot)co(dot)jp> |
Cc: | pgsql-hackers(at)postgresql(dot)org |
Subject: | Re: Why are default encoding conversions |
Date: | 2006-03-28 16:24:51 |
Message-ID: | 2734.1143563091@sss.pgh.pa.us |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Tatsuo Ishii <ishii(at)sraoss(dot)co(dot)jp> writes:
>> Well, being able to switch to a different conversion is fine, but I don't
>> think that's a good argument for tying it to the schema search path.
> If it does work, then it's ok. However still I'm not sure why current
> method is evil.
Because with the current definition, any change in search_path really
ought to lead to repeating the lookup for the default conversion proc.
That's a bad idea from a performance point of view and I don't think
it's a particularly good idea from the definitional point of view
either --- do you really want the client conversion changing because
some function altered the search path?
> BTW, what does the standard say about conversion vs. schema? Doesn't
> conversion belong to schema? If so, then schema specific default
> conversion seems more standard-friendly way.
AFAICT we invented the entire concept of conversions ourselves. I see
nothing about CREATE CONVERSION in the SQL spec. There is a CREATE
TRANSLATION in SQL2003, which we'd probably not seen when we invented
CREATE CONVERSION, but it does *not* have a DEFAULT clause. I don't
think you can point to the spec to defend our current method of
selecting which conversion to use.
regards, tom lane
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2006-03-28 16:27:10 | Re: [GENERAL] PANIC: heap_update_redo: no block |
Previous Message | Jim C. Nasby | 2006-03-28 16:12:09 | Re: [GENERAL] PANIC: heap_update_redo: no block |