On Wed, Mar 20, 2013 at 5:38 PM, W. Matthew Wilson <matt@xxxxxxxxxx> wrote: > I got this table right now: > > select * from market_segment_dimension_values ; > +--------------------------+---------------+ > | market_segment_dimension | value | > +--------------------------+---------------+ > | geography | north | > | geography | south | > | industry type | retail | > | industry type | manufacturing | > | industry type | wholesale | > +--------------------------+---------------+ > (5 rows) > > The PK is (market_segment_dimension, value). > > The dimension column refers to another table called > market_segment_dimensions. > > So, "north" and "south" are to values for the "geography" dimension. > > In that data above, there are two dimensions. But sometimes there could be > just one dimension, or maybe three, ... up to ten. If the number of dimensions is not fixed, then you'll probably have to write a plpgsql function to first interrogate the data set for how many dimensions there are and then to build an n-dimension query. While joining a variable number of tables may be problematic as you won't have a fixed number of columns, using a union might give you what you want with a fixed number of columns. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
