BUG #2942: information_schema.element_types: documentation error

The following bug has been logged online:

Bug reference:      2942
Logged by:          Kirill Simonov
Email address:      xi@gamma.dn.ua
PostgreSQL version: 8.2
Operating system:   Linux
Description:        information_schema.element_types: documentation error
Details:

The page
http://www.postgresql.org/docs/8.2/interactive/infoschema-element-types.html

contains obsolete information.

The example query
SELECT c.column_name, c.data_type, e.data_type AS element_type
FROM information_schema.columns c LEFT JOIN information_schema.element_types
e
     ON ((c.table_catalog, c.table_schema, c.table_name, 'TABLE',
c.dtd_identifier)
       = (e.object_catalog, e.object_schema, e.object_name, e.object_type,
e.array_type_identifier))
WHERE c.table_schema = '...' AND c.table_name = '...'
ORDER BY c.ordinal_position;
fails with ERROR:  column e.array_type_identifier does not exist.

The fix is to replace 'e.array_type_identifier' with e'dtd_identifier'.

The column array_type_identifier described in the Table 32-17 does not
exists.

The column dtd_identifier, which is described as "This is currently not
useful.", should have he description of the former array_type_identifier
column.