An apparatus, method and data structure for generating at least one table in a broadcast environment, are provided. The apparatus includes a generator to generate an event information table (EIT) and an extended text table (ETT). The ETT has program guide information for an n-hour span and has a transmission interval. The ETT has a transmission interval and program description information according to the EIT. The transmission interval of the EIT is shorter than the transmission interval of the ETT.