⟩ How To Add a New Column to an Existing Table with "ALTER TABLE ... ADD" in MS SQL Server?
If you have an existing table with existing data rows, and want to add a new column to that table, you can use the "ALTER TABLE ... ADD" statement. The tutorial script below shows you a good example:
ALTER TABLE tip ADD author VARCHAR(40)
GO
sp_columns tip
GO
TABLE_OWNER TABLE_NAME COLUMN_TABLE TYPE_NAME ...
dbo tip id int ...
dbo tip subject varchar ...
dbo tip description varchar ...
dbo tip create_date datetime ...
dbo tip author datetime ...
SELECT * FROM tip
GO
id subject description create_date author
1 Learn SQL Visit www.rendc.org 2008-05-01 NULL
This SQL script added a new column called "author" to the "tip" table. NULL values were added to this column on all existing data rows.
