一、在已有数据表中,添加一个约束,但不让这个约束使用到已存在的数据中,在执行ALTER TABLE语句添加时使用WITH NOCHECK子句,这样新增的约束就不会去约束已存在的数据,而只会对新增的数据进行约束检查: alter table [tablename] with nochek add constraint [ ck_XXX] check (核查条件) 二、NOCHECK还可以禁用约束,...
-- add CHECK constraint without nameALTERTABLEOrdersADDCHECK(amount >0); Here's how we can add a namedCHECKconstraint. For example, -- add CHECK constraint named amountCKALTERTABLEOrdersADDCONSTRAINTamountCKCHECK(amount >0); Notes: If we try to add theCHECKconstraintamount > 0to a column t...
CHECK约束作为CREATE TABLE 语句的一部分进行指定,而规则以单独的对象创建,然后绑定到列上。 下例创建一个规则,执行与前面主题中的CHECK约束示例相同的功能。SQL Srver2005 首选的方法是 CHECK 约束。 CREATE RULE id_chk AS @id BETWEEN 0 and 10000 GO CREATE TABLE cust_sample ( cust_id int PRIMARY KEY,...
(15) ) --Table must have a CHECK Constraint ALTER TABLE single_partition WITH CHECK ADD CONSTRAINT CK_single_partition CHECK (col1 > 100) INSERT INTO single_partition VALUES (101,’Description’) INSERT INTO single_partition VALUES (102,’Description’) INSERT INTO single_partition VALUES (103...
)GO--foreign key constraintALTERTABLE[dbo].[Child1]WITHCHECKADDCONSTRAINT[FK_Child1_Parent]FOREIGNKEY([ParentID])REFERENCES[dbo].[Parent]([ParentID])ONDELETECASCADEGO--foreign key constraintALTERTABLE[dbo].[Child2]WITHCHECKADDCONSTRAINT[FK_Child2_Parent]FOREIGNKEY([ParentID])REFERENCES[dbo].[Pare...
问WITH CHECK ADD CONSTRAINT后跟CHECK CONSTRAINT与ADD CONSTRAINTEN最近在做新生入学系统，学生表中包括...
check database recovery mode is simple or full? check expiration date of SQL Server Evaluation Check if FullText Catalog exists (SQL SERVER 2008 R2) Class does not support aggregation Closed Sockets? cluster resource 'quorum' of type 'physical disk' in clustered role 'cluster group' failed Coll...
Without the CHECK_CONSTRAINTS hint, any CHECK, and FOREIGN KEY constraints are ignored, and after the operation the constraint on the table is marked as not-trusted. Note UNIQUE, PRIMARY KEY, and NOT NULL constraints are always enforced. At some point, you need to check the constraints on ...
Hi, Community. The SQL server is new to me. I am still learning. I needed to remove a user from the database, when I tried to remove it I got the below...
Here is an example of the range constraint placed on the Orders_6 temporary table. Again, the actual key values given are driven by the input data:複製 ALTER TABLE ORDERS_6 WITH CHECK ADD CONSTRAINT check_ORDERS_6 CHECK (O_ORDERKEY >= 535714275 AND O_ORDERKEY <= 642857124) ...