删除外键和恢复外键

最新推荐文章于 2022-05-10 11:49:10 发布

原创最新推荐文章于 2022-05-10 11:49:10 发布 · 1.1k 阅读

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本文提供了SQL语句示例，展示如何删除和恢复数据库表之间的外键约束。包括了针对不同表的具体操作命令，有助于理解外键在数据库维护中的应用。

创建数据库的时候sql语句会有生成外键的语句：

//删除外键
alter table t_user_roles drop constraint fk_t_user_r_reference_t_user;
alter table t_city_manager drop constraint fk_t_city_m_reference_t_user;	
alter table t_attention drop constraint fk_t_attent_reference_t_user;
alter table t_bus_demand drop constraint fk_t_bus_de_reference_t_user;
alter table t_quote drop constraint fk_t_quote_reference_t_suppli;

//恢复外键
ALTER TABLE ONLY t_attention
    ADD CONSTRAINT fk_t_attent_reference_t_user FOREIGN KEY (w3_account) REFERENCES t_user(w3_account) ON UPDATE RESTRICT ON DELETE RESTRICT;

ALTER TABLE ONLY t_bus_demand
    ADD CONSTRAINT fk_t_bus_de_reference_t_user FOREIGN KEY (w3_account) REFERENCES t_user(w3_account) ON UPDATE RESTRICT ON DELETE RESTRICT;

ALTER TABLE ONLY t_city_manager
    ADD CONSTRAINT fk_t_city_m_reference_t_user FOREIGN KEY (w3_account) REFERENCES t_user(w3_account) ON UPDATE RESTRICT ON DELETE RESTRICT;

ALTER TABLE ONLY t_quote
    ADD CONSTRAINT fk_t_quote_reference_t_suppli FOREIGN KEY (supplier_id) REFERENCES t_supplier(supplier_id) ON UPDATE RESTRICT ON DELETE RESTRICT;

ALTER TABLE ONLY t_user_roles

    ADD CONSTRAINT fk_t_user_r_reference_t_user FOREIGN KEY (w3_account) REFERENCES t_user(w3_account) ON UPDATE RESTRICT ON DELETE RESTRICT;