Re: libpq: possible to get list of tables, fields, and types?

john heasley wrote:

>using libpq, is it possible to get a list of tables (psql: \d equivalent),
>list of fields for each of those tables (psql: \d <table>), and types for
>each of the fields for a given container?
>
>there doesnt seem to be a way to do any of these, except for getting the
>field type of a returned tuple with PQftype() and looking up the returned
>oid in the pg_attribute.
>
>it does appear to be possible to query system tables (psql: \dS) for some
>of this data, such as pg_tables for a list of tables.  yet there doesnt
>appear to be a way to associate these entries to a particular datbase
>container.  am i missing some way to glue these tables together to get a
>list of tables per-container and fields per-table?
>
>tia,
>-heas
>
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Hi,

yes - system tables is the right answer.

pg_tables is a view on pg_class. And pg_class has the information you
need. Look into the developers guide for a description of systemtables.

Information about the attributes are in pg_attribute. Just join it with
pg_class:
  select relname, attname, atttypid, attlen from pg_attribute join
pg_class on attrelid = pg_class.oid

A good source for information is pgaccess. It is a TCL-script. You can
find examples in the source.


Tommi