SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 2)
    Identifier a
    Function equals (children 1)
     ExpressionList (children 2)
      Identifier _database
      Function currentDatabase (children 1)
       ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier t_distr
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier a
