Insert a new column in sql

To insert a new column in SQL, you can use the ALTER TABLE statement with the ADD COLUMN clause. The syntax is as follows:

ALTER TABLE table_name
ADD COLUMN new_column_name data_type;

Here:

• table_name is the name of the table where you want to add the new column.
• new_column_name is the name of the new column you want to add.
• data_type is the data type of the new column (e.g. INT, VARCHAR, DATE, etc.).

For example, to add a new column called age with a data type of INT to a table called employees, you would use the following SQL statement:

ALTER TABLE employees
ADD COLUMN age INT;

This will add a new column called age with a data type of INT to the employees table.

You can also specify additional options, such as:

• NULL or NOT NULL to specify whether the column can contain null values.
• DEFAULT to specify a default value for the column.
• UNIQUE or PRIMARY KEY to specify that the column is unique or a primary key.

For example:

ALTER TABLE employees
ADD COLUMN age INT NOT NULL DEFAULT 0;

This will add a new column called age with a data type of INT, not null, and a default value of 0.

Note that you can only add a new column to the end of the table, and you cannot add a new column to a table that is already being used by another process.