Problem $26$

Create a MYSQL trigger named trg$\_$updatecustbalance to update the CUST$\_$BALANCE in the CUSTOMER table when a new invoice record is entered. $($Assume that the sale is a credit sale.$)$ Whatever value appears in the INV$\_$AMOUNT column of the new invoice should be added to the customer's balance. Test the trigger using the following new INVOICE record, which would add $225\mathrm{.}40$ to the balance of customer $1001$:

INV$\_$NUM CUST$\_$NUM INV$\_$DATE INV$\_$AMOUNT

$8005,1001,2022-04-27225\mathrm{.}40$