UPDATE

UPDATE is a SQL statement in the DML Statements category. Modifies existing rows in a table. Always use WHERE to avoid updating all rows. The syntax is UPDATE table_name SET column1 = value1, column2 = value2 WHERE condition;. It returns number of rows affected. A typical example: UPDATE employees SET salary = salary * 1.1 WHERE department = 'IT'; -- 10% raise for IT department -- Update multiple columns: UPDATE products SET price = 49.99, updated_at = NOW() WHERE id = 123; A close relative is INSERT INTO, which inserts new rows into a table. A close relative is DELETE, which removes rows from a table. Always use WHERE to avoid deleting all rows. A close relative is REPLACE INTO, which iNSERT, but if a UNIQUE/PRIMARY KEY conflict exists, DELETES the old row and inserts a new one. MySQL-specific. More about this category: Data Manipulation Language — INSERT, UPDATE, DELETE, REPLACE, MERGE.