Re: Overriding derived values

CREATE TABLE Discounts
(player_id CHAR(15) NOT NULL
REFERENCES Players (player_id)
ON DELETE CASCADE
ON UPDATE CASCADE,
start_date DATETIME DEFAULT CURRENT_TIMESTAMP NOT NULL,
end_date DATETIME,
discount_percent DECIMAL (3,2) DEFAULT 0.00 NOT NULL,
CHECK (start_date < end_date),
PRIMARY KEY (player_id, start_date));

Use a NULL to represent "eternity" and use a stored procedure to add
one-month rows based on the bowler's average.

If they are not on the "permanent bad guy list" as shown by (end_date
IS NULL), then leave the row until it is manually overridden.

.

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