SQL Server：检查约束以检查客户是否超过18(SQL Server : check constraint to check customers are over 18)

 我正在使用SQL Server Management Studio，并希望创建一个表，当日期输入到表中时，它会检查某人是否超过18。 
 
 我有： 
 
CREATE TABLE tCustomer
(
    FirstName VARCHAR(20) NOT NULL,
    DateOfBirth DATE CHECK (DateOfBirth < GETDATE())
);
 
 我知道目前这是错误的，因为它正在检查DateOfBirth是否小于当前时间。 但我似乎无法找到我想要的东西。 
 
 如果它对于创建表太复杂，可能是某种触发器？ 我真的不想使用存储过程。 
 
 非常感谢您的帮助。 
 
 干杯。 

I am using SQL Server Management Studio and would like to create a table that when dates are entered in to the table, it checks that someone is over 18.
 
I have got as far as:
 
CREATE TABLE tCustomer
(
    FirstName VARCHAR(20) NOT NULL,
    DateOfBirth DATE CHECK (DateOfBirth < GETDATE())
);
 
I know this is currently wrong as all it is doing is checking that the DateOfBirth is less than the current time. But I can't quite seem to find what I am looking for.
 
If it is too complex for create table, maybe some sort of trigger? I do not really want to use a stored procedure.
 
Your help would be appreciated.
 
Cheers. 

原文：https://stackoverflow.com/questions/23041681