updating tables while preserving business rules - sql

Question

i have the following scenario , business rules and database schema , i want to update customer and salesrep tables by using just SQL while preserving business rules.how can i do that.
scenario:
suppose Premier Products wants to give all their customer and sales
reps a Christmas bonus. All customers will have their balance owing reduced
by $100, and their amount on order increased by $50. The increased amount
on order flows on to their sales reps. But because of the limitation that a sales rep amount on order cannot exceed $1000 (BR4),
some sales reps will not get a bonus.
(a) how this can be achieved in pure SQL, while preserving all business rules.
BR1. The total amount owed by a customer cannot exceed their credit limit.
BR2. The sales rep's amount on order is incremented by the same amount as their customers.
BR3. All new customers are given a $100 credit, that is an initial balance of -$100.
BR4. A sales rep is not entitled to any commission on sales beyond $1000 on order.
/*-- SLSREP Table */
CREATE TABLE SLSREP
(SLSRNUMB DECIMAL(2),
TOTCOMM DECIMAL(7,2),
COMMRATE DECIMAL(3,2) CONSTRAINT CK_commrate CHECK( commrate BETWEEN 0 AND 1),
AMOUNTONORDER DECIMAL(9,2),
CONSTRAINT PK_SLSREP PRIMARY KEY (SLSRNUMB));
/*-- Customer Table */
CREATE TABLE CUSTOMER
(CUSTNUMB DECIMAL(3),
BALANCE DECIMAL(7,2) ,
CREDLIM DECIMAL(5) CONSTRAINT NN_credlim NOT NULL ,
SLSRNUMB DECIMAL(2) ,
AMOUNTONORDER DECIMAL(9,2) ,
CONSTRAINT PK_CUSTOMER PRIMARY KEY (CUSTNUMB),
CONSTRAINT FK_CUSTOMER_slsrnumb FOREIGN KEY (SLSRNUMB) REFERENCES SLSREP,
CONSTRAINT CK_credit CHECK (balance + AMOUNTONORDER <= credlim));

Answer 1

These requirements seem to be in conflict.
Premier Products wants to give all
their customer and sales reps a
Christmas bonus.
But because of the limitation that a
sales rep amount on order cannot
exceed $1000 (BR4), some sales reps
will not get a bonus.
BR4. A sales rep is not entitled to
any commission on sales beyond $1000
on order.
I would model a bonus as a bonus, not as a commission on sales. A bonus isn't a commission or an order; they're all different things. So I propose two new business rules.
BR5. A bonus is not a commission.
BR6. A bonus is not an order.
Here's one way to implement a table of sales rep bonuses.
CREATE TABLE SLSREPBONUS (
SLSRNUMB DECIMAL(2) REFERENCES SLSREP (SLSRNUMB),
BONUSDT DATE,
BONUSAMT DECIMAL(7,2) NOT NULL CHECK (BONUSAMT BETWEEN 1 AND 1000),
CONSTRAINT PK_SLSREP PRIMARY KEY (SLSRNUMB, BONUSDT)
);
Your customer table has only aggregate amounts, so I'd assume that you'd have to issue a credit in some other part of your accounting system. I'd hope that if you did that, the customers aggregates would be updated properly. (But I have to say I've learned that hope doesn't scale well.)