Re: VARIANT / ANYTYPE datatype - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: VARIANT / ANYTYPE datatype
Date
Msg-id 4DC1AF17.8020701@dunslane.net
Whole thread Raw
In response to Re: VARIANT / ANYTYPE datatype  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: VARIANT / ANYTYPE datatype  (Merlin Moncure <mmoncure@gmail.com>)
List pgsql-hackers

On 05/04/2011 01:36 PM, Tom Lane wrote:
>
>> The main idea is to be able to store column values in an audit table
>> like this:
>> old_value    variant
>> new_value    variant
>> Currently, they use text for old_value and new_value, but this is, of
>> course, not very satisfactory.
> Just out of curiosity, what actual functionality gain would ensue over
> just using text?  It seems like doing anything useful with the audit
> table contents would still require casting the column to text, or the
> moral equivalent of that.
>

Yeah, I've been down this road once or twice, and I think that's the $64 
question.

I wrote a custom audit app two or three years ago. After several 
iterations the customer and I found that using an hstore for the old/new 
(or old record / changeset, which is what we actually use) was the most 
suitable for our use.

I think if we did this we'd need to add some sort of is_type()  and 
typeof() functions for variant objects.

cheers

andrew


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