SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Identifier a
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Function merge (children 1)
       ExpressionList (children 2)
        Function REGEXP (children 1)
         ExpressionList (children 1)
          Literal \'\\0a\'
        Literal \'^t$\'