2. 添加外键 alter table orders add foreign key(goods_id) references goods(sid) on update cascade on delete cascade; on update cascade: 被引用行更新时,引用行自动更新; on update restrict: 被引用的行禁止更新; on delete cascade: 被引
on delete no action --当删除student的记录的时候 会失败 on update cascade --但更新student的记录时 sc3表中的记录也会更新 ) ; --恰当使用级联更新和级联删除 方便数据库在更新时的操作; insert into student(sno) values('2014019'); insert into sc3 values('2014019','001',100); delete from studen...
is_active | boolean | not null | plain 8 | |falseIndexes:"table_name_pkey"PRIMARY KEY, btree (id) Foreign keys:"table_name_user_id_fkey"FOREIGN KEY (user_id) REFERENCES"users"(id) ON DELETE CASCADE ON UPDATE CASCADE Check constraints:"table_name_check_user_id"CHECK (user_id IS NOT...
createtableug(uidint, gidint, uptimevarchar(30));CREATETRIGGERt_ug_updateTime AFTERINSERTORUPDATEONugFOREACHROWEXECUTEPROCEDUREfunc_ug_updateTime(); 可以看到直接删除触发器函数时,如果该触发器函数被某个触发器依赖,那么就会报错,此时需要在删除触发器函数的时候,添加cascade参数,从而将该触发器函数与依赖与...
postgres(# ON UPDATE CASCADE ON DELETE RESTRICT postgres(# ); CREATE TABLE Here is the command to see the structure of the created table : postgres=# \d employeesTable"public.employees"Column|Type|Modifiers ---+---+--- employee_id|integer|not null first_name|character varying(20)|default...
ON UPDATE CASCADE ON DELETE CASCADE ) """, """ CREATE TABLE vendor_parts ( vendor_id INTEGER NOT NULL, part_id INTEGER NOT NULL, PRIMARY KEY (vendor_id , part_id), FOREIGN KEY (vendor_id) REFERENCES vendors (vendor_id) ON UPDATE CASCADE ON DELETE CASCADE, ...
DROP MATERIALIZED VIEW [ IF EXISTS ] name [ CASCADE | RESTRICT ]; 其中,IF EXISTS 可以避免删除一个不存在的物化视图时产生错误;CASCADE 表示级联删除依赖于该物化视图的对象;RESTRICT 表示如果存在依赖对象则提示错误信息,这是默认值。 我们可以使用以下语句删除物化视图 emp_stat_mv2: DROP MATERIALIZED VIEW ...
(part_id) ON UPDATE CASCADE ON DELETE CASCADE ) """, """ CREATE TABLE vendor_parts ( vendor_id INTEGER NOT NULL, part_id INTEGER NOT NULL, PRIMARY KEY (vendor_id , part_id), FOREIGN KEY (vendor_id) REFERENCES vendors (vendor_id) ON UPDATE CASCADE ON DELETE CASCADE, FOREIGN KEY (...
beigang=# grantall on schema csm_ca to public;GRANT beigang=# revoke all on schema csm_ca frompublic;REVOKE 8、先创建⼀个⾓⾊xxx，再创建⼀个超级⽤户csm、普通⽤户csm_ca，csm⽤户创建⼀个数据库testdb，在这个数据库⾥创建⼀个schema：csm_ca，然后赋予普通⽤户csm_ca操作数据库...
ENDASon_update, CASEconfdeltype WHEN'a'THEN'NO ACTION' WHEN'r'THEN'RESTRICT' WHEN'c'THEN'CASCADE' WHEN'n'THEN'SET NULL' WHEN'd'THEN'SET DEFAULT' ENDASon_delete, CASEconfmatchtype WHEN'u'THEN'UNSPECIFIED' WHEN'f'THEN'FULL' WHEN'p'THEN'PARTIAL' ...