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CREATE TABLE customer (cust_id VARCHAR2(10) PRIMARY KEY);
CREATE TABLE employee (id NUMBER PRIMARY KEY);
CREATE TABLE orderheader(
Order_id NUMBER CONSTRAINT or_id NOT NULL CHECK(Order_id > 0),
Order_date DATE,
Order_customer VARCHAR2(10) REFERENCES customer(Cust_id),
Order_delivery NUMBER CONSTRAINT or_deli NOT NULL CHECK (Order_delivery > 0),
Order_total NUMBER CONSTRAINT or_to CHECK (Order_total > 0),
Order_vat NUMBER,
Order_payment NUMBER,
Order_completed DATE,
Order_credit CHAR(1) CONSTRAINT or_cre_ck CHECK (Order_credit IN ('Y', 'N')),
Order_takenby NUMBER CONSTRAINT or_tak CHECK(Order_takenby > 0) REFERENCES employee,
CONSTRAINT orhe_id_cus_deli PRIMARY KEY (Order_customer, Order_delivery, Order_id)
)
DROP TABLE orderheader;
CREATE TABLE orderheader(
Order_id NUMBER
CONSTRAINT or_id_nn NOT NULL
CONSTRAINT or_id_ck CHECK(Order_id > 0),
Order_date DATE,
Order_customer VARCHAR2(10)
CONSTRAINT or_cust_fk REFERENCES customer(Cust_id),
Order_delivery NUMBER
CONSTRAINT or_deli_nn NOT NULL
CONSTRAINT or_deli_ck CHECK (Order_delivery > 0),
Order_total NUMBER
CONSTRAINT or_to_ck CHECK (Order_total > 0),
Order_vat NUMBER,
Order_payment NUMBER,
Order_completed DATE,
Order_credit CHAR(1)
CONSTRAINT or_cre_ck CHECK (Order_credit IN ('Y', 'N')),
Order_takenby NUMBER
CONSTRAINT or_tak_ck CHECK(Order_takenby > 0)
CONSTRAINT or_tak_fk REFERENCES employee,
CONSTRAINT orhe_id_cus_deli PRIMARY KEY (Order_customer, Order_delivery, Order_id)
)