title: Can PostgreSQL index array columns?
body: <p>I can't find a definite answer to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?</p>
  
  <p>I created a simple table with one <code>int[]</code> column, and put a unique index on it. I noticed that I couldn't add the same array of ints, which leads me to believe the index is a composite of the array items, not an index of each item.</p>
  
  <pre><code>INSERT INTO "Test"."Test" VALUES ('{10, 15, 20}');
  INSERT INTO "Test"."Test" VALUES ('{10, 20, 30}');
  
  SELECT * FROM "Test"."Test" WHERE 20 = ANY ("Column1");
  </code></pre>
  
  <p>Is the index helping this query?</p>