command to delete column in sql

The command to delete columns in SQL is ALTER TABLE DROP COLUMN, which is used to modify the table structure and delete specified columns. The steps include: 1. Specify the table name to be modified; 2. Use the DROP COLUMN clause to specify the column name to be deleted.

The command to delete a column in SQL

The command to delete a column in SQL isALTER TABLE, which allows the table to be modified Structure, including deleting columns.

Syntax:

<code class="sql">ALTER TABLE table_name DROP COLUMN column_name;</code>

Steps:

1. Specify the table name to be modified table_name.
2. Use the DROP COLUMN clause to specify the column name column_name to be deleted.

Example:

Suppose there is a table named employee that contains the following columns:

Column name	Data type
id	int
name	varchar(255)
age	int
address	text

To delete the address column, you can use the following command:

<code class="sql">ALTER TABLE employee DROP COLUMN address;</code>

Note:

• Only columns in the table that do not have foreign key constraints can be deleted.
• Deleting a column will permanently delete all data stored in that column.
• Make sure to back up the table before deleting columns in case of data loss.

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