How do I rename a column in a database table using SQL?

Renaming a column in a database table using SQL is a straightforward task, but the exact syntax can vary depending on the database system you are using. Changing column names is often necessary when you want your schema to be more descriptive, readable, or aligned with new business requirements.

In MySQL, you can use the ALTER TABLE command with the CHANGE keyword. However, you must also specify the column’s data type when renaming:

ALTER TABLE employees  

CHANGE COLUMN old_name new_name VARCHAR(100);

In PostgreSQL and Oracle, the syntax is simpler with the RENAME COLUMN clause:

ALTER TABLE employees  

RENAME COLUMN old_name TO new_name;

In SQL Server, you use the stored procedure sp_rename:

  EXEC sp_rename 'employees.old_name', 'new_name', 'COLUMN';

Key points to remember:

• Syntax differs by database → Always check your specific SQL dialect.
  
• Data type required in MySQL → When renaming with CHANGE, you must restate the column’s data type.
  
• Keep backups → Renaming columns in production should be done carefully, as it may break queries, views, or applications depending on the old name.
  
• Use meaningful names → Choose column names that clearly describe the data they hold.
  

By knowing the correct syntax for your SQL database, you can safely rename columns and keep your database schema consistent, organized, and easier to understand.