>>> Select countries.name, basel.year, basel.value, cites.year,
>>> cites.value
>>> From countries
>>> Left Join basel on basel.id_country = countries.id_country and
>>> basel.value=1
>>> Left Join cites on cites.id_country = countries.id_country and
>>> cites.value=1
>>
>> I would have thought so, but the query turns forever.
>
> How many rows in each of your tables, and what indexes do you have?
around 5000 rows
> You may also wish to review Andreas' suggestions as they propose a
> more sensible table structure rather than having a table for each
> convention.
The table proposal really looks nice. But our database is structured
by variable - so each convention has its own table.
> You may also be interested in the tablefunc contrib module to help
> present your data in the format you require rather than having a join
> for each convention:
Yes, I use this for the online representation of the data. Very useful
indeed.