How Do I Change Multiple Column Names in SQL?

Method 1: Using the ALTER TABLE Statement

Syntax:

ALTER TABLE table_name CHANGE COLUMN old_column_name new_column_name data_type;

Example:

Suppose we have a table called employees with the following structure:

Original Table – employees:

We want to rename the emp_first_name and emp_last_name columns to first_name and last_name, respectively, and change the data type of emp_salary to DECIMAL(10, 2).

SQL Query:

ALTER TABLE employees
    CHANGE COLUMN emp_first_name TO first_name VARCHAR(255),
    CHANGE COLUMN emp_last_name TO last_name VARCHAR(255),
    CHANGE COLUMN emp_salary TO emp_salary DECIMAL(10, 2);
    

Modified Table – employees:

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Method 2: Using the RENAME COLUMN Statement (PostgreSQL, MySQL)

Syntax:

ALTER TABLE table_name
    RENAME COLUMN old_column_name TO new_column_name;
    

Example:

Consider the same table employees as in the previous example, but this time, we’ll use PostgreSQL to rename the emp_first_name and emp_last_name columns to first_name and last_name, respectively.

SQL Query:

ALTER TABLE employees
    RENAME COLUMN emp_first_name TO first_name,
    RENAME COLUMN emp_last_name TO last_name;

Modified Table – employees:

These examples demonstrate two different methods to change multiple column names in SQL, using the ALTER TABLE statement and the RENAME COLUMN statement in PostgreSQL, MySQL respectively.