How can you add a column to a table in SQL Server?

9 months ago

Jackson Davis

2 minutes

To add a column to a table, you can use the ALTER TABLE statement.

The grammar is as follows:

ALTER TABLE table_name
ADD column_name data_type;

Here, table_name represents the name of the table to be modified, column_name is the name of the column to be added, and data_type is the data type of the new column.

For example, to add a new column called email to the table named customers with a data type of varchar(255), you can use the following statement:

ALTER TABLE customers
ADD email varchar(255);

Please note that when adding a new column, existing rows in the table will be automatically filled with default values. If you want to specify a default value, you can use the DEFAULT clause as shown below:

ALTER TABLE customers
ADD email varchar(255) DEFAULT 'unknown';

To allow a new column to have null values, you can specify the column constraint as NULL or NOT NULL. For example:

ALTER TABLE customers
ADD email varchar(255) NULL;

ALTER TABLE customers
ADD email varchar(255) NOT NULL;

You can also add new columns at specific positions in an existing table. To add a new column after another column, you can use the AFTER clause, as shown below:

ALTER TABLE customers
ADD email varchar(255) AFTER column_name;

To add a new column at the beginning of a table, you can use the FIRST clause, as shown below:

ALTER TABLE customers
ADD email varchar(255) FIRST;

Please select the appropriate syntax to add a column to the table based on actual needs.