How to Change (Update) Column Values in SQL

To change values in a column, you use the UPDATE statement.

Basic Syntax:

UPDATE table_nameSET column_name = new_valueWHERE condition;

• table_name: The table to update.

• column_name: The column whose value you want to change.

• new_value: The new value to assign.

• WHERE: Specifies which rows to update. Without it, all rows are updated!

Examples:

1. Update a single row

UPDATE employeesSET salary = 60000WHERE employee_id = 101;

2. Update multiple rows

UPDATE employeesSET status = 'inactive'WHERE last_login < '2023-01-01';

3. Update multiple columns

UPDATE employeesSET salary = 70000, status = 'active'WHERE employee_id = 102;

Important:

• Always use a WHERE clause unless you want to update all rows.

• You can use expressions or subqueries for new values, e.g.:

UPDATE employeesSET salary = salary * 1.1WHERE department = 'Sales';

If you want help with a specific update query or database, let me know!