The following script contains the SQL statements for this query:
-- Find the most active stocks in the "COMPUTER" industry -- for last three days. commit; SELECT st.INSTRUMENT_ID, st.TRADING_SYMBOL, SUM(TRADE_SIZE) TRADESIZE, DENSE_RANK() OVER (ORDER by SUM(TRADE_SIZE) DESC) as RANKING FROM STOCK_TRADE st inner join INSTRUMENT ii on ii.INSTRUMENT_ID = st.INSTRUMENT_ID inner join SCND_IDST_CLS sc on ii.SCND_IDST_CLS_ID = sc.SCND_IDST_CLS_ID and sc.SIC_NAME = 'COMPUTERS' WHERE st.TRADE_DATE BETWEEN '2005-11-10' AND '2005-11-14' GROUP BY st.INSTRUMENT_ID ,st.TRADING_SYMBOL ;