Message-Id: <m11GhGe-0000dbC@druid.net>
Subject: Re: [INTERFACES] A few more JDBC meta-data questions...
In-Reply-To: <37B8A5B4.A85541A0@phalanx.net> from Mark Dzmura at "Aug 16,
	1999 11:58:44 pm"
To: mdz@phalanx.phalanx.net (Mark Dzmura)
Date: Tue, 17 Aug 1999 07:19:00 -0400 (EDT)
From: "D'Arcy" "J.M." Cain <darcy@druid.net>
Cc: pgsql-interfaces@postgreSQL.org
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Thus spake Mark Dzmura
> 1. Is it possible to programatically enumerate or discover the databases in a running database??
> 
> 2. Is it possible to programmaticaly enumerate or discover the tables in a database??

-- get list of databases                             
SELECT datname FROM pg_database;                     
    
-- get list of tables including views but not system tables
SELECT relname FROM pg_class
    WHERE relkind = 'r' AND                          
        relname !~ '^Inv' AND     
        relname !~ '^pg_';
    
And for completeness;                                
    
-- get list of attributes and types for a specific table
SELECT pg_attribute.attname, pg_type.typname
    FROM pg_class, pg_attribute, pg_type
    WHERE pg_class.relname = 'tablename' AND         
        pg_attribute.attnum > 0 AND
        pg_attribute.attrelid = pg_class.oid AND     
        pg_attribute.atttypid = pg_type.oid; 
    
-- get list of tables and primary keys (assumes no complex keys)
-- only includes tables with primary keys so no views
SELECT pg_class.relname, pg_attribute.attname        
    FROM pg_class, pg_attribute, pg_index    
    WHERE pg_class.oid = pg_attribute.attrelid AND
        pg_class.oid = pg_index.indrelid AND
        pg_index.indkey[0] = pg_attribute.attnum AND
        pg_index.indisprimary = 't';

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.