Re: How to reject overlapping timespans?

Am 17.02.2013 19:20, schrieb Andreas Kretschmer:
> Andreas <maps.on@gmx.net> hat am 17. Februar 2013 um 18:02 geschrieben:
>> I need to store data that has a valid timespan with start and enddate.
>>
>> objects ( id, name, ... )
>> object_data ( object_id referencs objects(id), startdate, enddate, ... )
>>
>> nothing special, yet
>>
>> How can I have PG reject a data record where the new start- or enddate
>> lies between the start- or enddate of another record regarding the same
>> object_id?
> With 9.2 you can use DATERANGE and exclusion constraints
>
> test=# create table maps(id int, duration daterange, exclude using gist(id with
> =, duration with &&));
> NOTICE:  CREATE TABLE / EXCLUDE will create implicit index
> "maps_id_duration_excl" for table "maps"
> CREATE TABLE
> test=*# insert into maps values (1,'(2013-01-01,2013-01-10]');
> INSERT 0 1
> test=*# insert into maps values (1,'(2013-01-05,2013-01-15]');
> ERROR:  conflicting key value violates exclusion constraint
> "maps_id_duration_excl"
> DETAIL:  Key (id, duration)=(1, [2013-01-06,2013-01-16)) conflicts with existing
> key (id, duration)=(1, [2013-01-02,2013-01-11)).
> test=*#


though I still have a 9.1.x as productive server so I'm afraid I have to 
find another way.

Thanks, Andreas   :)