Add an Sn for the read data in oracle

Add a sequence number for the read data in oracle. When we demonstrate the Report to the customer, the customer sometimes puts it in the first column of the report, can I add a serial No. www.2cto.com? But if I modify the program code, it can be implemented. However, it will be troublesome to do so and there is a practical solution, the RowNum function in ORACLE is used to obtain the data. For example, select id and name from tablename can be used to display the data required by the customer. Then, select rownum, id, name from tablename is used to read the sequence number and the data to be displayed. Then, you only need to add a field to the report (fastreport or other reports) to display the information.