I have a mysql database that has the column balance. This table is used for storing data about a user's account balance, so how to add numbers in mysql statement?
here is what I have so far
$sql_data = "UPDATE `database1`.`users` SET (`balance`) = '(what to put here?)'
WHERE ('" . $mysqlid . "') ";
so do I have to a) retrieve the current balance with a mysql select query? and b) what do I use to add the integer 5 to the column balance, the mysql row is double(16,2)
$sql_data = "UPDATE `database1`.`users` SET `balance` = MIN(`balance` + 5, (maximum_value_they_can_have)) WHERE ('" . $mysqlid . "') ";
Edit:
Arguably you can do a check to verify that balance + 5 doesn't go over the bounds of the balance data-type in PHP using something that is unlikely to run into issues, like bcmath functions. (Does math via given precision with string comparison)
Try this :
$bal=100.5; // balance to be add
$sql_data = "UPDATE `database1`.`users` SET `balance` = (`balance`+'$bal') WHERE ('" . $mysqlid . "') ";
You can do this:
$sql_data = "UPDATE `database1`.`users` SET `balance` = (`balance` + [value to be added]) WHERE ('" . $mysqlid . "') ";
