On 20/03/14 13:28, Josh Berkus wrote:
>> 3. relation limit - possibility to set session limit for maximum size of
>> relations. Any relation cannot be extended over this limit in session, when
>> this value is higher than zero. Motivation - we use lot of queries like
>> CREATE TABLE AS SELECT .. , and some very big results decreased a disk free
>> space too much. It was high risk in our multi user environment. Motivation
>> is similar like temp_files_limit.
>
> I'd think the size of the relation you were creating would be difficult
> to measure. Also, would this apply to REINDEX/VACUUM FULL/ALTER? Or
> just CREATE TABLE AS/SELECT INTO?
>
Also I think this would probably only make sense for TEMPORARY tables -
otherwise you can get this sort of thing going on:
- you create a table and you have set a relation size limit
- you commit and keep working
- I add a whole lot of rows to your new table (taking it over the limit)
- you go to add some more rows to this table...
Should you now be stopped working? Does this feature need to track *who*
added which chunks of a table (suspect very difficult to do sensibly)?
Regards
Mark