UPDATE command is used to modify an existing record in the table.
Syntax:-
UPDATA table_name SET column_1=new_value_1, column_2=new_value_2, column_3=new_value_3 ................... ................... column_n=new_value_n WHERE [CONDITION]
Example:-
Suppose you have two records in the employees table
SELECT * FROM employees
Output:-
+----+------------+-----------+----------------+------------+ | id | first_name | last_name | email | address | +----+------------+-----------+----------------+------------+ | 1 | Virat | Kohli | virat@abc.com | Delhi | | 2 | rohit | Sharma | rohit@abc.com | Mumbai | +----+------------+-----------+----------------+------------+
Apply WHERE Condition
FIRST CASE:- Now, You want to update the address of Virat from Delhi to Mumbai
UPDATE employees SET address='Mumbai' where id=1
Now, check the table
+----+------------+-----------+----------------+------------+ | id | first_name | last_name | email | address | +----+------------+-----------+----------------+------------+ | 1 | Virat | Kohli | virat@abc.com | Mumbai | | 2 | rohit | Sharma | rohit@abc.com | Mumbai | +----+------------+-----------+----------------+------------+
Without WHERE Condition
SECOND CASE:- If you do not use where condition then the record will be update in all rows.
Example:- If you want to update email of rohit@abc.com to rohitsharma@abc.com without where condition.
UPDATE employees SET email='rohitsharma@abc.com'
Now check the updated results in the employees table
SELECT * FROM employees
Output:-
+----+------------+-----------+----------------+------------+ | id | first_name | last_name | email | address | +----+------------+-----------+----------------+------------+ | 1 | Virat | Kohli | rohitsharma@abc.com | Mumbai| | 2 | rohit | Sharma | rohitsharma@abc.com | Mumbai| +----+------------+-----------+----------------+------------+