CREATE TABLE STORES (
STORE_ID NUMBER(10) NOT NULL,
SUPPLIER_NAME VARCHAR2(40) NOT NULL,
CONSTRAINT STORES_PK PRIMARY KEY (STORE_ID));
CREATE TABLE PRODUCTS (
PRODUCT_ID NUMBER(10) NOT NULL,
PRODUCT_NAME VARCHAR2(30) NOT NULL,
SUPPLIER_ID NUMBER(10) NOT NULL,
STORE_ID NUMBER(10) NOT NULL,
CONSTRAINT
FK_STORES FOREIGN KEY (STORE_ID) REFERENCES STORES(STORE_ID) ON DELETE CASCADE);
刪除stores的記錄,products也刪除.
=================================
-- 創建測試主表. ID 是主鍵.
CREATE TABLE test_main (
id INT,
value VARCHAR(10),
PRIMARY KEY(id)
);
-- 創建測試子表.
CREATE TABLE test_sub (
id INT,
main_id INT,
value VARCHAR(10),
PRIMARY KEY(id)
);
-- 創建外鍵(使用 ON DELETE CASCADE 選項,刪除主表的時候,同時刪除子表)
ALTER TABLE test_sub
ADD CONSTRAINT main_id_cons
FOREIGN KEY (main_id) REFERENCES test_main ON DELETE CASCADE;
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