 <p>One of the ways to do this could be create "anchor" table from all possible data from all three tables and then use <code>left outer join</code>:</p> <pre><code>select A.column2, B.column2, C.column2 from ( select distinct month from table1 union select distinct month from table2 union select distinct month from table3 ) as X left outer join table1 as A on A.month = X.month left outer join table2 as B on B.month = X.month left outer join table3 as C on C.month = X.month </code></pre>