title: List columns with indexes in PostgreSQL
body: <p>I would like to get the columns that an index is on in PostgreSQL. </p>
  
  <p>In MySQL you can use <code>SHOW INDEXES FOR table</code> and look at the <code>Column_name</code> column. </p>
  
  <pre><code>mysql&gt; show indexes from foos;
  
  +-------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
  | Table | Non_unique | Key_name            | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
  +-------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
  | foos  |          0 | PRIMARY             |            1 | id          | A         |       19710 |     NULL | NULL   |      | BTREE      |         | 
  | foos  |          0 | index_foos_on_email |            1 | email       | A         |       19710 |     NULL | NULL   | YES  | BTREE      |         | 
  | foos  |          1 | index_foos_on_name  |            1 | name        | A         |       19710 |     NULL | NULL   |      | BTREE      |         | 
  +-------+------------+---------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
  </code></pre>
  
  <p>Does anything like this exist for PostgreSQL?</p>
  
  <p>I've tried <code>\d</code> at the <code>psql</code> command prompt (with the <code>-E</code> option to show SQL) but it doesn't show the information I'm looking for.</p>
  
  <p><strong>Update:</strong> Thanks to everyone who added their answers. <a href="https://stackoverflow.com/users/48044/cope360">cope360</a> gave me exactly what I was looking for, but several people chimed in with very useful links. For future reference, check out the documentation for <a href="http://www.postgresql.org/docs/current/static/catalog-pg-index.html" rel="noreferrer">pg_index</a> (via <a href="https://stackoverflow.com/users/15785/milen-a-radev">Milen A. Radev</a>) and the very useful article <a href="http://www.alberton.info/postgresql_meta_info.html" rel="noreferrer">Extracting META information from PostgreSQL</a> (via <a href="https://stackoverflow.com/users/22595/michal-niklas">Michał Niklas</a>).</p>