SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 5)
    Identifier mutation_id
    Identifier command
    Identifier parts_to_do_names
    Identifier parts_to_do
    Identifier is_done
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.mutations
   Function equals (children 1)
    ExpressionList (children 2)
     Identifier database
     Function currentDatabase (children 1)
      ExpressionList
