Is this doable using Postgresql crosstab or some otherfunction?

 Hi folkes,
 this is my first message on this list.
 I have quite a challenging problem and my own skills seem not to be
 adequate for resolving it.
 I have a relational model where the basic idea is to store data
 vertically instead using traditional horizontal approach. So instead of
 having a row in a table with n columns, I have n rows with value columns
 for different data types. This makes the model very dynamic but also
 difficult to use. I try to describe the (simplified) core of the model
 (or at least the parts which have some meaning) in the following pseudo
 definition:

 Table values
  ID serial pk
  instanceID integer fk1 (never mind this)
  parametertypeID integer fk2
  value_integer integer
  value_varchar character varying
  value_date date
  stamp timestamp

 Table parameters
  parametertypeID serial pk
  typeid integer fk1
  parameternameID integer fk2

 Table parameternames
  paramaternameID serial pk
  parametername character varying
  parameterdatatype integer or like enum(1,2,3) (this defines whether to
 use value_integer, value_varchar or value_date)


 From these three tables I would like to create a select statement where
 the response is the following (where parameters.typeid = x and
 values.timestamp = dd.mm.yyyy hh.mm.ss.xx)

 instanceID integer
 parameternames.parametername#1, value and datatype from value_integer,
 value_varchar or value_date
 parameternames.parametername#2, value and datatype from value_integer,
 value_varchar or value_date
 ...
 parameternames.parametername#n, value and datatype from value_integer,
 value_varchar or value_date


 Quite challanging, right?


 - mika -