class OCI8

def exec_internal(sql, *bindvars)
  begin
    cursor = parse(sql)
    ret = cursor.exec(*bindvars)
    case cursor.type
    when :select_stmt
      if block_given?
        cursor.fetch { |row| yield(row) }   # for each row
        ret = cursor.row_count()
      else
        ret = cursor
        cursor = nil # unset cursor to skip cursor.close in ensure block
        ret
      end
    when :begin_stmt, :declare_stmt # PL/SQL block
      if block_given?
        ary = []
        cursor.keys.sort.each do |key|
          ary << cursor[key]
        end
        yield(*ary)
      else
        ret
      end
    else
      ret # number of rows processed
    end
  ensure
    cursor.nil? || cursor.close
  end
end # exec