SQL DEFAULT Constraint. The DEFAULT constraint is used to set a default value for a column. The default value will be added to all new records, if no other value is specified.

You can use following syntax, For more information see this question and answers : Add a column with a default value to an existing table in SQL Server. Syntax : ALTER TABLE {TABLENAME} ADD {COLUMNNAME} {TYPE} {NULL|NOT NULL} CONSTRAINT {CONSTRAINT_NAME} DEFAULT {DEFAULT_VALUE} WITH VALUES Example :

Feb 4, 2025 · You can use SQL Server Management Studio (SSMS) to specify a default value that is entered into the table column. You can set a default by using the Object Explorer, or by executing Transact-SQL. If you don't assign a default value to the column, and the user leaves the column blank, then:

Sep 18, 2008 · What this will do is add the column as a nullable field and with the default value, update all fields to the default value (or you can assign more meaningful values), and finally it will change the column to be NOT NULL.

Apr 2, 2009 · SELECT COALESCE(column_name, default_value) FROM table_name; You also could read an article which compares COALESCE and ISNULL.

Feb 8, 2025 · Learn how to assign a default value to a column in SQL. Ensure consistency in your database with default values for new entries.

In SQL, the DEFAULT constraint is used to set a default value if we try to insert an empty value into a column. college_id INT PRIMARY KEY, college_code VARCHAR(20), college_country VARCHAR(20) DEFAULT 'US' . Here, the default value of the college_country column is US.

Jun 9, 2023 · The default value is the value used when no value is provided for an Insert or an Update statement. Using the DEFAULT keyword will create a “default constraint” on the table. You can add a default constraint either when creating a table or after the table already exists.

Oct 27, 2024 · Learn how to use the SQL DEFAULT constraint to automatically assign default values to columns when no value is specified during INSERT operations. This comprehensive guide provides detailed explanations, practical examples, and best practices for effective database design.

Jul 6, 2024 · In this article, we’ve learned how to set and remove default values for an existing column in SQL Server, PostgreSQL, and MySQL. Additionally, we saw that the syntax for updating a default value can vary based on the DBMS.