sql - Get the aggregate column values in JSP when using group-by -

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i have problem when retrieving data sql using jsp.

resultset rs = statement.executequery("select orderdate,                                                sum(orderingcost)                                           `shopping`.`order`                                       group orderdate"); int count = 0; //string  while (rs.next()) {   //string orderdate = rs.getstring("orderdate");   //string orderingcost = rs.getstring("orderingcost");   system.out.println(count);   count++; }

i use group statement group data.

however, don't know how data out when group applied.

can me?

you need alias column:

select orderdate, sum(orderingcost) orderingcost `shopping`.`order` group orderdate

then you'll have column named orderingcost in resultset, , can do:

double orderingcost = rs.getfloat("orderingcost") // need getfloat instead of string since it's numeric value

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