The benchmark Sensex today advanced by 57 points to end at all-time high of 31,804.82 and the Nifty closed above the 9,800-mark for the first time as banking, oil & gas and auto stocks advanced

Mumbai: The benchmark Sensex today advanced by 57 points to end at all-time high of 31,804.82 and the Nifty closed above the 9,800-mark for the first time as banking, oil & gas and auto stocks advanced.      Optimistic buying in blue-chip stocks ahead of release of industrial production data for May and retail inflation for June drove stocks higher. The BSE Sensex had opened on a better note at 31,813.24 and rose to the day's high of 31,865.69 in early trade. However, some profit booking in recent gainers pulled the index down to a day's low of 31,731.43 points. The BSE barometer finally closed at a new closing high of 31,804.82, up 57.73 points, or 0.18 per cent.     The 50-share Nifty index of the National Stock Exchange also ended 30.05 points, or 0.31 per cent, higher at new closing peak of 9,816.10. During the session, Nifty shuttled between 9,824.95 and 9,787.70.      Shares of index heavyweight Reliance Industries rallied 1.06 per cent to hit nine-year high of Rs 1,511 after its subsidiary Reliance Jio yesterday announced new tariff plans to retain subscribers.      Stocks of ONGC topped the gainers list in the Sensex kitty by surging 2.06 per cent to Rs 163.60 on reports that the proposed ONGC-HPCL deal will be completed by the end of FY18. Other contributers to the key indices were Hind Unilever, ICICI Bank, SBI, Tata Motors, Power Grid, NTPC, Adani Ports, Bharti Airtel, Tata Steel, Axis Bank and Maruti Suzuki. PTI