title: Slick 2.0 "returning" an element is not working for H2 database
body: <p>The following code seqment should insert a new entry and return it (with auto generated id). It works fine for PostgreSQL.</p>
  
  <pre><code>val ret = elementTableQuery.returning(elementTableQuery) += Element("Arg1", "Arg2", "Arg3")
  </code></pre>
  
  <p>The Exception which is thrown is:</p>
  
  <pre><code>JdbcSQLException: Invalid value "2" for parameter "columnIndex" [90008-172] (DbException.java:329)
  org.h2.message.DbException.getJdbcSQLException(DbException.java:329)
  org.h2.message.DbException.get(DbException.java:169)
  org.h2.message.DbException.getInvalidValueException(DbException.java:215)
  org.h2.jdbc.JdbcResultSet.checkColumnIndex(JdbcResultSet.java:3088)
  org.h2.jdbc.JdbcResultSet.get(JdbcResultSet.java:3116)
  org.h2.jdbc.JdbcResultSet.getString(JdbcResultSet.java:279)
  ch.xxx.test.data.ElementCreator$.create(InitialDataCreator.scala:199)
  </code></pre>
  
  <p>The statement also works (in PorstgreSQL and H2) if I remove the "returning" part. It also works if I only return the generated Id like:</p>
  
  <pre><code>val ret = elementTableQuery.returning(elementTableQuery.map(_.id)) += Element("Arg1", "Arg2", "Arg3")
  </code></pre>
  
  <p>I found a bug report (<a href="https://github.com/slick/slick/issues/230" rel="nofollow">https://github.com/slick/slick/issues/230</a>) which seems to concern the same problem but was closed because it could not be reproduced.</p>
  
  <p>Should  I open a new bug? Is there anything wrong with my query?</p>
  
  <p>I am thankful for any input.</p>