Sum in array with match value

I would like to do a simple sum per salesid in php - mysql after cross calculation between date (2 tables) to get the real time commission, all the value already come out correctly but I have a problem with the final sum per sales id.

Every time there is a change in the input commission form, the new value is inserted:

salesid  commission  datefrom - dateto
aa0001   20%         2010/01/01 - 2010/02/09
aa0001   25%         2010/02/09 - null

and table transac开发者_开发百科tion got

items   qty   price   salesid    transactiondate

call value of the table commission where salesid=$_sessionid $today = date in php next week.

if ($dateto == 0) {
$dateto = $today; }

call value of the table transaction where salesid=$_sessionid

I use below range to get the commssion with transaction date:

if ($transactiondate >= $datefrom and $transactiondate < $dateto) {
$subcommission = ($price * $commission) } 

and the value come like below:

salesid  commission
aa0001   1000
bb0001   500
aa0001   200
bb0001   50

I already try with few sample in this web but still cannot meet the correct result. I cannot do the sum in mysql because of some reason (need calculation with other table)

the result will be:

aa0001  1200
bb0001  550

I appreciate any help to complete the test. Thank you so much.

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If that's supposed to represent a table with salesid and commission columns, you can just do:

SELECT salesid, SUM(commission) FROM table GROUP BY salesid;

Even if it depends on a join you should be able to do it, but lacking details I can't really give an example

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You can create an array which key is salesid and value is commission and then again filter array for same key. it may help u.

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I not too expert with php, because I truely vb programmer. And I not too expert using index, key, or multiple array.

I have solve this problem with using temp table for store temporary data with session. everytime the form open, will be delete data in temp table with session userid and make calculation data and insert to temp table and do the select the data again with sum and group by.

Thank for all of you support and I will learn more from now on.... nice day bro..