Add default value of datetime field in SQL Server to a timestamp

Question

I\'ve got a table that collects forms submitted from our website, but for some reason, when they created the table, they didn\'t put a timestamp in the table. I want it to e

Answer 1

Let's say you create a database table for a registration system.

IF OBJECT_ID('dbo.registration_demo', 'U') IS NOT NULL 
  DROP TABLE dbo.registration_demo; 

CREATE TABLE dbo.registration_demo (
    id INT IDENTITY PRIMARY KEY,
    name NVARCHAR(8)
);

Now a couple people register.

INSERT INTO dbo.registration_demo (name) VALUES
    ('John'),('Jane'),('Jeff');

Then you realize you need a timestamp for when they registered.

If this app is limited to a geographically localized region, then you can use the local server time with GETDATE(). Otherwise you should heed Tanner's consideration for the global audience with GETUTCDATE() for the default value.

Add the column with a default value in one statement like this answer.

ALTER TABLE dbo.registration_demo
ADD time_registered DATETIME DEFAULT GETUTCDATE();

Let's get another registrant and see what the data looks like.

INSERT INTO dbo.registration_demo (name) VALUES
    ('Julia');

SELECT * FROM dbo.registration_demo;

id    name    time_registered
1     John    NULL
2     Jane    NULL
3     Jeff    NULL
4     Julia   2016-06-21 14:32:57.767