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

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 enter the exact date and time that the record was entered.
I know it's in there somewhere, but I can't seem to find how to set the default value (like in Access, you use getNow() or Now()) but I don't know where to put it.

For modifying an existing column in an existing table:
ALTER TABLE YourTable ADD CONSTRAINT DF_YourTable DEFAULT GETDATE() FOR YourColumn

This can also be done through the SSMS GUI.
Put your table in design view (Right click on table in object explorer->Design)
Add a column to the table (or click on the column you want to update if it already exists)
In Column Properties, enter (getdate()) in Default Value or
Binding field as pictured below

In that table in SQL Server, specify the default value of that column to be CURRENT_TIMESTAMP.
The datatype of that column may be datetime or datetime2.
e.g.
Create Table Student
(
Name varchar(50),
DateOfAddmission datetime default CURRENT_TIMESTAMP
);

While the marked answer is correct with:
ALTER TABLE YourTable ADD CONSTRAINT DF_YourTable DEFAULT GETDATE() FOR YourColumn
You should always be aware of timezones when adding default datetime values in to a column.
Say for example, this datetime value is designed to indicate when a member joined a website and you want it to be displayed back to the user, GETDATE() will give you the server time so could show discrepancies if the user is in a different locale to the server.
If you expect to deal with international users, it is better in some cases to use GETUTCDATE(), which:
Returns the current database system timestamp as a datetime value. The database time zone offset is not included. This value represents the current UTC time (Coordinated Universal Time). This value is derived from the operating system of the computer on which the instance of SQL Server is running.
ALTER TABLE YourTable ADD CONSTRAINT DF_YourTable DEFAULT GETUTCDATE() FOR YourColumn
When retrieving the values, the front end application/website should transform this value from UTC time to the locale/culture of the user requesting it.

Disallow Nulls on the column and set a default on the column of getdate()
/*Deal with any existing NULLs*/
UPDATE YourTable SET created_date=GETDATE() /*Or some sentinel value
'19000101' maybe?*/
WHERE created_date IS NULL
/*Disallow NULLs*/
ALTER TABLE YourTable ALTER COLUMN created_date DATE NOT NULL
/*Add default constraint*/
ALTER TABLE YourTable ADD CONSTRAINT
DF_YourTable_created_date DEFAULT GETDATE() FOR created_date

The syntax for this when creating a new table is:
CREATE TABLE MyTable
(
MYTableID INT IDENTITY(1,1),
CreateDate DATETIME NOT NULL CONSTRAINT DF_MyTable_CreateDate_GETDATE DEFAULT GETDATE()
)

This works for me...
ALTER TABLE [accounts]
ADD [user_registered] DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ;

This also works:
CREATE TABLE Example(
...
created datetime default GETDATE()
);
Or:
ALTER TABLE EXAMPLE ADD created datetime default GETDATE();

This worked for me. I am using SQL Developer with Oracle DB:
ALTER TABLE YOUR_TABLE
ADD Date_Created TIMESTAMP DEFAULT CURRENT_TIMESTAMP NOT NULL;

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

To make it simpler to follow, I will summarize the above answers:
Let`s say the table is called Customer
it has 4 columns/less or more...
you want to add a new column to the table where every time when there is insert... then that column keeps a record of the time the event happened.
Solution:
add a new column, let`s say timepurchase is the new column, to the table with data type datetime.
Then run the following alter:
ALTER TABLE Customer ADD CONSTRAINT DF_Customer DEFAULT GETDATE() FOR timePurchase

In SQLPlus while creating a table it is be like as
SQL> create table Test
( Test_ID number not null,
Test_Date date default sysdate not null );
SQL> insert into Test(id) values (1);
Test_ID Test_Date
1 08-MAR-19

Related

Trying to set a column not null and add a default constraint in one statement

Currently I have a column named CreatedDate in a Shipper table I created. It is nullable. My task is to change the created date to be a required field, not allow nulls, and have a default of GetDate(). This has to be done in a single query... Keep in mind there is no data in my table yet. I've tried the following code and I can't seem to get it to work. This is a homework assignment and I'm only looking for guidance. Any help would be greatly appreciated. Thanks in advance.
USE Business
ALTER TABLE Shipper
ALTER COLUMN CreatedDate date NOT NULL
CONSTRAINT CNDefaultCreatedDate
DEFAULT GETDATE() For CreatedDate;
Two different statements, I assume this is SQL Server:
--Add the default
ALTER TABLE [Shipper] --What table
ADD CONSTRAINT [def_createddate] --Give the constraint a name
DEFAULT GETDATE() FOR [CreatedDate]; --default of what for which column
--Set to not allow NULL
ALTER TABLE [Shipper] --What table
ALTER COLUMN [CreatedDate] DATE NOT NULL; --altering what column and either NULL or NOT NULL
Understand adding a default will not update existing data. I know you mentioned your table does not have data, but in the future the null values must be updated to some value before the ALTER COLUMN NOT NULL is allowed.
Here's reference to the MS documentation ALTER TABLE
If the column did not already exist you can add it, set it not null and then even update existing rows in one statement:
--If Shipper did not already have the column CreatedDate
ALTER TABLE [Shipper]
ADD [CreatedDate] DATE NOT NULL
CONSTRAINT [def_createddate] DEFAULT GETDATE()
WITH VALUE --if column is nullable use this and it will update existing records with the default. It column is NOT NULL this is applied by default.
Have you tried this:
USE Business
ALTER TABLE Shipper
ALTER COLUMN CreatedDate date NOT NULL DEFAULT GETDATE();

Is it possible to insert timestamp in sql?

I want to have a column in which the default timestamp is added when an insertion is done. I have done that in MySQL using choosing default timestamp option. How do I do that in SQL Server?
ALTER TABLE table_name ADD InsertTime DATETIME DEFAULT GETDATE()
ALTER TABLE [table] ADD [CreationTimeStampUTC] DATETIME DEFAULT(GETUTCDATE())
Or you could do the same with GETDATE(), which I think I've seen more in real-world code. Note, of course, that GETDATE() will be valued with the current server time of the SQL Server, and may or may not match up with the current time of the web server if you have one, or particularly the client's machine. Obviously there's no issue with that, just make sure you're aware of the implications ahead of time. You could also store this timestamp as a DATETIMEOFFSET to rid yourself of some of those concerns, but since you're speaking explicitly of on-server default values, I think UTC is perfectly sufficient.
What you're looking for is a default constraint. How you add it depends on whether the column already exists or not. If it doesn't, you can add the column and the constraint in one shot like so:
alter table dbo.yourTable
add [NewColumn] datetime
constraint [DF_NewColumn] default (getdate());
If the column already exists, you can attach a default to it like so:
alter table dbo.yourTable
add constraint [DF_ExistingColumn] default (getdate()) for [ExistingColumn];
Finally, if the table doesn't yet exist, you can add the constraint to the table definition:
create table dbo.yourTable (
NewColumn datetime not null constraint [DF_NewColumn] default (getdate())
)
Note: in all cases, I gave the constraint a name. You can choose not to, but then you'll eventually get a huffy DBA asking why her database comparison is a mess because the constraint names don't match up between dev and prod. :)

SQL Server time stamp column insertion or updation possible explicitly?

Is there any way to provide an explicit value for time stamp column in a table in SQL server? I am aware it is not datetime column but I want to know whether there is any way to insert or update it explicitly.
You cannot insert/update to timestamp column explicitly. They are generated automatically, when you perform insert/update to the table.
Because the timestamps appear to be representations of timestamps created by the database when you inserted or updated the column, in effect you would have to change the original timestamp created by the database in order to define them explicitly.
From your second comment I appreciate that you might have data coming in which is already timestamped and you just want those represented on your table in the same way as inserting data with "set identity_insert on" .
The answer would be to select the existing table into another table then add the incoming data. If you run the code below I think you'll see what I mean.
create table abc
(
col1 int, timestamp
)
go
insert into abc(col1) values (1)
go
select col1,convert(varbinary,timestamp) timestamp# into def from abc
go
select * from abc
select * from def
As far as I know the timestamp represents a row version number (which is why they change when you update a value in the row because you are creating another version of the row). There might be a date in the transaction log which states when this version of the row came into being. I don't consider it possible to directly convert timestamp to datetime.
Well..the only other idea I have is to add another column and then select the timestamp values into that! The weirdest thing, in doing this it takes the last character back one! See what you think.
drop table abc
go
create table abc
(
col1 int, timestamp
)
go
insert into abc(col1) values (1)
go
alter table abc add timestamp# varbinary(18)
go
update abc set timestamp# = convert(varbinary,timestamp)
Generaly speaking, when creating a table I would include a column which defaults to datetime, this way you have a datetime when each row is created.
Like this:
drop table def
go
create table def
(
col1 int,
idt datetime default getdate()
)
If you insert a value into col1 and do not include the idt in your column list in the insert statement the idt column will default to the datetime you inserted the value.
Like this:
insert into def (col1) values (1)

Automatic Adding Current DateTime In TableField

I am using SQL SERVER 2005 and i am also newbie to SQL SERVER
now i need to know that is there any way or any technique in SQL SERVER 2005
such that as soon as i add new record in table then current date-time should be added in to any given field of table.
Example:
Suppose i have CUSTOMER table
and it has fields say CustomerID,CustomerName,....,DateTime.
now whenever new customer added in this table then current date-time should be automatically added in to DateTime Field of CUSTOMER table.
In SSMS one can set the Default value or binding property of the appropriate column of the table property to getdate().
You need to add default constraint:
alter table MyTable add constraint MyColumnDefault default getdate() for MyColumn;
I'm not much of an expert in SQL but you could use TIMESTAMP for this, see:
http://msdn.microsoft.com/en-us/library/ms182776%28v=sql.90%29.aspx
It sounds like you should have a look at the timestamp data type:
http://msdn.microsoft.com/en-us/library/ms182776%28v=sql.90%29.aspx
Check table definition with default value
Declare #Table Table
(
Id int identity,[Name] varchar(100),CreatedDate DateTime default (Getdate())
)
insert into #Table([Name])
values ('yogesh')
insert into #Table ([Name])
values ('Bhadauriya')
insert into #Table ([Name])
values ('Yogesh Bhadauriya')
select *
From #Table

How to write sql to set alter a column's default value in sql server 2005?

I have a table [Product] with a column [CreateTime] datetime null, and is has some data already.
How can I set the column [CreateTime] 's default value to getdate(), and make the new added data to have a default value getdate() for column [CreateTime].
You cannot change a default - you will need to first drop it, and then recreate it.
In order to drop it, you need to know its name, and then use
ALTER TABLE dbo.Product
DROP CONSTRAINT yourOldDefaultConstraint
Once you've done that, you can add a new default constraint, and in order to apply it to existing rows, use the "WITH VALUES" part:
ALTER TABLE dbo.Product
ADD CONSTRAINT NewDefaultConstraintName
DEFAULT GetDate() FOR CreateTime WITH VALUES
Oops - sorry, the "WITH VALUES" only seems to work if you create a DEFAULT constraint at the time you create the table, or if you add the column - it doesn't seem to get applied to an existing column.
In this case you would just have to follow your ALTER TABLE statement with something like this:
UPDATE dbo.T_Product
SET CreateTime = GETDATE()
WHERE CreateTime IS NULL
That should do the trick, too!
Marc

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