![]() ![]() ![]() ![]() +-+-+-+-+-+-+ MCQ Practice competitive and technical Multiple Choice Questions and Answers (MCQs) with simple and logical explanations to prepare for tests and interviews. Specify the column name in the INSERT INTO clause and use the DEFAULT keyword in the VALUES clause. Now we can check the default value of the ‘age’ column, by running the following command. If you want to insert a default value into a column, you have two ways: Ignore both the column name and value in the INSERT statement. Here is an example: ALTER TABLE Employee ALTER COLUMN age SET DEFAULT 0 To add a default value to a column in MySQL, use the ALTER TABLE … ALTER COLUMN … SET DEFAULT statement. | Address | varchar | Yes | | New York | |Īdd a default value to a column that already exists | EmpID | int | No | PRI | NULL | auto_increment | | Field | Type | Null | Key | Default | Extra | Now we can check the default value of the column ‘Address’, by running the following command. The default value will be added to all new records, if no other value is specified. Alter table Employee ADD(Address Varchar(10) Default 'New York') The DEFAULT constraint is used to set a default value for a column. If you define a UNIQUE constraint without specifying a name, MySQL automatically generates a name for it. In the example below, by using ALTER, the column “Address” is added with a default value “New York” to “Employee” table. MySQL uses the combination of values in both column columnname1 and columnname2 to evaluate the uniqueness. When adding a column to a table using ALTER, we can also specify a default value. Suppose you have a table with three columns: CREATE TABLE MyTable ( And you put a row into it, using all its default values: INSERT INTO MyTable () VALUES (). In this tutorial, we are going to see how to add a column with a default value and how to add a default value to a column that already exists in a MySQL table. ![]()
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