CREATE TABLE table_name
(
  column1 datatype null/not null,
  column2 datatype null/not null,
  ...
  CONSTRAINT constraint_name CHECK (column_name condition) [DISABLE]
);

create table tb_supplier
(
 supplier_id    number,
 supplier_name   varchar2(50),
 contact_name   varchar2(60),
 /*定义CHECK约束，该约束在字段supplier_id被插入或者更新时验证，当条件不满足时触发。*/
 CONSTRAINT check_tb_supplier_id CHECK (supplier_id BETWEEN 100 and 9999)
);

--supplier_id满足check约束条件，此条记录能够成功插入
insert into tb_supplier values(200, 'dlt','stk');
 
--supplier_id不满足check约束条件，此条记录能够插入失败，并提示相关错误如下
insert into tb_supplier values(1, 'david louis tian','stk');

Error report -
SQL Error: ORA-02290: check constraint (502351838.CHECK_TB_SUPPLIER_ID) violated
02290. 00000 - "check constraint (%s.%s) violated"
*Cause:  The values being inserted do not satisfy the named check

create table tb_products
(
 product_id    number not null,
 product_name   varchar2(100) not null,
 supplier_id    number not null,
 /*定义CHECK约束check_tb_products,用途是限制插入的产品名称必须为大写字母*/
 CONSTRAINT check_tb_products
 CHECK (product_name = UPPER(product_name))
);

--product_name满足check约束条件，此条记录能够成功插入
insert into tb_products values(2, 'LENOVO','2');
--product_name不满足check约束条件，此条记录能够插入失败，并提示相关错误如下
insert into tb_products values(1, 'iPhone','1');

SQL Error: ORA-02290: check constraint (502351838.CHECK_TB_PRODUCTS) violated
02290. 00000 - "check constraint (%s.%s) violated"
*Cause:  The values being inserted do not satisfy the named check

ALTER TABLE table_name
ADD CONSTRAINT constraint_name CHECK (column_name condition) [DISABLE];

drop table tb_supplier;
--创建实例表
create table tb_supplier
(
 supplier_id    number,
 supplier_name   varchar2(50),
 contact_name   varchar2(60)
);

--创建check约束
alter table tb_supplier
add constraint check_tb_supplier
check (supplier_name IN ('IBM','LENOVO','Microsoft'));

--supplier_name满足check约束条件，此条记录能够成功插入
insert into tb_supplier values(1, 'IBM','US');
 
--supplier_name不满足check约束条件，此条记录能够插入失败，并提示相关错误如下
insert into tb_supplier values(1, 'DELL','HO');

SQL Error: ORA-02290: check constraint (502351838.CHECK_TB_SUPPLIER) violated
02290. 00000 - "check constraint (%s.%s) violated"
*Cause:  The values being inserted do not satisfy the named check

ALTER TABLE table_name
ENABLE CONSTRAINT constraint_name;

drop table tb_supplier;
--重建表和CHECK约束
create table tb_supplier
(
 supplier_id    number,
 supplier_name   varchar2(50),
 contact_name   varchar2(60),
 /*定义CHECK约束，该约束尽在启用后生效*/
 CONSTRAINT check_tb_supplier_id CHECK (supplier_id BETWEEN 100 and 9999) DISABLE
);
 
--启用约束
ALTER TABLE tb_supplier ENABLE CONSTRAINT check_tb_supplier_id;

CREATE TABLE [dbo].[Test2007](
  [ProductReviewID] [int] IDENTITY(1,1) NOT NULL,
  [ReviewDate] [datetime] NOT NULL
) ON [PRIMARY]
 
GO
 
ALTER TABLE [dbo].[Test2007] WITH CHECK ADD CONSTRAINT [CK_Test2007] CHECK (([ReviewDate]>='2007-01-01' AND [ReviewDate]'2007-12-31'))
GO
 
ALTER TABLE [dbo].[Test2007] CHECK CONSTRAINT [CK_Test2007]
GO
 
CREATE TABLE [dbo].[Test2008](
  [ProductReviewID] [int] IDENTITY(1,1) NOT NULL,
  [ReviewDate] [datetime] NOT NULL
) ON [PRIMARY]
 
GO
 
ALTER TABLE [dbo].[Test2008] WITH CHECK ADD CONSTRAINT [CK_Test2008] CHECK (([ReviewDate]>='2008-01-01' AND [ProductReviewID]'2008-12-31'))
GO
 
ALTER TABLE [dbo].[Test2008] CHECK CONSTRAINT [CK_Test2008]
GO
 
INSERT INTO [Test2008] values('2008-05-06')
INSERT INTO [Test2007] VALUES('2007-05-06')
 
CREATE VIEW testPartitionView
AS
SELECT * FROM Test2007
UNION
SELECT * FROM Test2008
 
SELECT * FROM testPartitionView
WHERE [ReviewDate]='2007-01-01'
 
SELECT * FROM testPartitionView
WHERE [ReviewDate]='2008-01-01'
 
SELECT * FROM testPartitionView
WHERE [ReviewDate]='2010-01-01'

ALTER TABLE table_name
DISABLE CONSTRAINT constraint_name;

--禁用约束
ALTER TABLE tb_supplier DISABLE CONSTRAINT check_tb_supplier_id;

--查看约束的详细信息
select
constraint_name,--约束名称
constraint_type,--约束类型
table_name,--约束所在的表
search_condition,--约束表达式
status--是否启用
from user_constraints--[all_constraints|dba_constraints]
where constraint_name='CHECK_TB_SUPPLIER_ID';

ALTER TABLE table_name
DROP CONSTRAINT constraint_name;

ALTER TABLE tb_supplier
DROP CONSTRAINT check_tb_supplier_id;