SQL UPDATE Statement

Introduction

SQL UPDATE statement is used to modify the data already present in the database.

Syntax:

UPDATE table_name
SET Column1= value1, Cloumn2 = value2, column3 = value3.....
WHERE [Condition];

Example : Query using UPDATE statement.
Consider the following table titled as 'Clients'

Client_ID	Last_Name	First_Name	Contact	Country
1	Thomas	Alex	2400000	USA
2	Cruise	Martin	5600000	USA
3	Pandit	Prajakta	null	India

1. Write a query to update contact information of a particular row where condition is given as, client id = 3.

UPDATE Clients
SET Contact = 34542892
WHERE Client_ID = 3 AND LAST_Name = 'Pandit';

The result is shown in the following table.

Client_ID	Last_Name	First_Name	Contact	Country
1	Thomas	Alex	2400000	USA
2	Cruise	Martin	5600000	USA
3	Pandit	Prajakta	34542892	India

2. Write a query to perform update operation on multiple fields from given table (titled as Clients) below.

Client_ID	Last_Name	First_Name	Contact	Country
1	Thomas	Alex	2400000	USA
2	Cruise	Martin	5600000	USA
3	Pandit	Prajakta	34542892	India

UPDATE Clients
SET LAST_Name = 'Brown', First_name = 'Albert', Contact = 923849, Country = 'UK'
WHERE Client_ID = 3;

The result is shown in the following table.

Client_ID	Last_Name	First_Name	Contact	Country
1	Thomas	Alex	2400000	USA
2	Cruise	Martin	5600000	USA
3	Brown	Albert	923849	UK