Re: Patch for SQL-Standard Interval output and decoupling DateStyle from IntervalStyle - Mailing list pgsql-hackers

Tom Lane wrote:
> Ron Mayer <rm_pg@cheapcomplexdevices.com> writes:
> 
>> (3) Put something into the dump file that will make the old
>>      server reject the file rather than successfully loading
>>      wrong data?   (Some "if intervalstyle==std and version<8.3
>>      abort loading the restore" logic?)
> 
> There isn't any way to do that, unless you have a time machine in
> your hip pocket.  The trouble with putting
>     set intervalstyle = something;
> into the dump script is that older servers will (by default) report
> an error on that line and keep right on chugging.

Not necessarily.  Couldn't we put
 select * from (select substring(version() from '[0-9\.]+') as version) as a join (select
generate_series(0,100000000000))as b on(version<'8.4');
 
 set intervalstyle = something;

Or something similar in the dump file.