<?php
// Esta función debería ser necesaria, ya que una conexión PostgreSQL se
// vincula a una base de datos.
function pg_list_dbs($db)
{
    assert(is_resource($db));
    $query = '
SELECT
 d.datname as "Name",
 u.usename as "Owner",
 pg_encoding_to_char(d.encoding) as "Encoding"
FROM
 pg_database d LEFT JOIN pg_user u ON d.datdba = u.usesysid
ORDER BY 1;
';
    return pg_query($db, $query);
}

// Listar las tablas.
function pg_list_tables($db)
{
    assert(is_resource($db));
    $query = "
SELECT
 c.relname as \"Name\",
 CASE c.relkind WHEN 'r' THEN 'table' WHEN 'v' THEN 'view' WHEN 'i' THEN 'index' WHEN 'S' THEN 'sequence' WHEN 's' THEN 'special' END as \"Type\",
  u.usename as \"Owner\"
FROM
 pg_class c LEFT JOIN pg_user u ON c.relowner = u.usesysid
WHERE
 c.relkind IN ('r','v','S','')
 AND c.relname !~ '^pg_'
ORDER BY 1;
";
    return pg_query($db, $query);
}

// Ver también pg_meta_data(). Esto devuelve la definición de los campos como array.
function pg_list_fields($db, $table)
{
    assert(is_resource($db));
    $query = "
SELECT
 a.attname,
 format_type(a.atttypid, a.atttypmod),
 a.attnotnull,
 a.atthasdef,
 a.attnum
FROM
 pg_class c,
 pg_attribute a
WHERE
 c.relname = '".$table."'
 AND a.attnum > 0 AND a.attrelid = c.oid
ORDER BY a.attnum;
";
    return pg_query($db, $query);
}
?>