SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function count (children 1)
     ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier tab1
   Function in (children 1)
    ExpressionList (children 2)
     Identifier id
     Subquery (children 1)
      SelectWithUnionQuery (children 1)
       ExpressionList (children 1)
        SelectQuery (children 2)
         ExpressionList (children 1)
          Identifier filter_id
         TablesInSelectQuery (children 1)
          TablesInSelectQueryElement (children 1)
           TableExpression (children 1)
            TableIdentifier tab2
