php math? possible to add rows together?

[jake66]

my database currently looks like this:
Date: apr 5 06
Vendor: ph
Tax: 2.00
Cost: 100.00

Date: mar 5 06
Vendor: ph
Tax: 3.00
Cost: 250.00

how can i add all values of cost and tax together, like so:
Tax Cost: 5.00
Total Cost: 350.00
Grand Total: $450.00

any tutorial sites i was able to find didn't have anything to do with php

[inveni0]

Make sure they are type INT and use the SUM command.

[jake66]

not sure how to call or use the SUM command?

[coopster]

Or just add them.

SELECT 
 myDate, 
 myVendor, 
 myTax, 
 myCost, 
 myTax + myCost AS myTotal 
 FROM myTable 
;

[inveni0]

Use it in a query. Check PHP.net, I think they have more information.

[jake66]

coopster, i tried:
$sql = "select tax, cost tax + cost as total from wholesale";
and
$sql = "select date, vendor, tax, cost, tax + cost as total from wholesale";
and
$sql = "select SUM(tax) from wholesale";

but no result (the table shows as empty) or just simply doesn't show anything.

for coopster's suggestion, once i got it to select properly i tried echo $total; but it didn't show anything either

[jake66]

i have achieved desired effect by the following:
$sumtax += $row[tax];
$sumcost += $row[cost];

now, i'm wondering if it's possible to add $sumtax and $sumcost together for the grand total?

[jake66]

desired effect achieved by the following:
$grandtotal = $sumtax + $sumcost;

thanks for your help everybody

[coopster]

Sorry about that jake66, you are correct. I was showing you a way to accummulate a total per line whereas you were looking for final totals. My mistake. Yes, accummulating them as you show here would be the easiest way to do that. I usually initialize the total values to zero first.

$totalTax  = 0; // initialize 
$totalCost = 0; // initialize 
while (looping through the result set) { 
 $totalTax  += $row['tax']; 
 $totalCost += $row['cost']; 
} 
$grandTotal = $totalTax + $totalCost;

[jake66]

thank you coopster :)

i am having a problem: this is not allowing me decimals? i went into the database and changed tax and cost's "type" to decimal and it still shows as a whole number. is there anyway i can fix this?

[coopster]

number_format [php.net]?

[jake66]

the problem seems to be when it's going to the database, it's not being saved as a decimal.. the latter two digits and the period disappear

[jake66]

fixed my problem by changing the field types back to "text"

why would "decimal" prevent it being shown as a decimal?

[coopster]

Which database are you using?

[jake66]

not sure what you're asking?
but it's mysql

[coopster]

How did you define the column when you were defining it as DECIMAL? Did you give it a precision and scale? If you did not specify the scale it will default to 0. You can read more about MySQL DECIMAL numeric types here:

[dev.mysql.com...]