SELECT count(*) FROM gsscode_types;
 count 
-------
   206
(1 row)

SELECT description('E01000001'::gsscode);
          description           
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT description('E01');
          description           
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT description('e01');           -- case insensitive
          description           
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT description('E01000001');     -- longer text truncates to 3 chars
          description           
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT description('K02'::text);
  description   
----------------
 United Kingdom
(1 row)

SELECT description('K03'::text);
  description  
---------------
 Great Britain
(1 row)

SELECT description('K04'::text);
    description    
-------------------
 England and Wales
(1 row)

SELECT description('S01'::text);
 description 
-------------
 Data Zones
(1 row)

SELECT description('W01'::text);
          description           
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT description('ZZ'::text) IS NULL;  -- unknown prefix
 ?column? 
----------
 t
(1 row)

-- whole-row form
SELECT (type_info('E01000001'::gsscode)).name;
              name              
--------------------------------
 Lower layer Super Output Areas
(1 row)

SELECT (type_info('E01000001'::gsscode)).abbreviation;
 abbreviation 
--------------
 LSOA
(1 row)

SELECT (type_info('K02'::text)).name;
      name      
----------------
 United Kingdom
(1 row)

SELECT (type_info('K02'::text)).theme;
     theme      
----------------
 Administrative
(1 row)

SELECT type_info('ZZ'::text) IS NULL;  -- unknown prefix
 ?column? 
----------
 t
(1 row)