Dynamic view or temp table in Postgres?

[oppcos]

Hi,
I'm suffering from some db ignorance. I was trying to do the following in another database and found that I couldn't and wanted to know if Postgres is able. Essentially I'm trying to rotate a table for the purpose of my view. Here's an example.

First, I have a table like this:

 _________   ________   _____   _____
[prime_key] [Field_ID] [Field] [Class]
 ---------   --------   -----   -----
         1         1A   'foo'     'A'
         2         2A   'bar'     'A'
         3         1A   'tst'     'B'
         4         3A   'hi.'     'B'

I am trying to create a sql statement that returns this data rearranged into a view or temp table that utilizes the Class for its headers so it looks like this:

 ________       _       _   
[Field_ID]     [A]     [B]
 --------   -----   -----
       1A   'foo'   'tst'
       2A   'bar'    null
       3A    null   'hi.'

There could be many different 'Class'es and I want the columns returned to be dynamic according to however many Classes are set and using the Field_ID for the primary key of the newly created view/table. Hope that makes sense. Is Postgres the way to go?

Thanks!