SQL UPDATE Statement

The SQL UPDATE Statement

The UPDATE statement is used to modify the existing records in a table.

UPDATE Syntax

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition

Demo Database

Below is a selection from the "Customers" table in the Northwind sample database:

SQL UPDATE Table Example

The following SQL statement updates the first customer (CustomerID = 1) with a new contact person and a new city.

UPDATE Customers 
SET ContactName = 'Alfred Schmidt', City = 'Frankfurt' 
WHERE CustomerID = 1

The selection from the "Customers" table will now look like this:

SQL UPDATE Multiple Records Example

It is the WHERE clause that determines how many records will be updated.

The following SQL statement will update the ContactName to "Juan" for all records where country is "Mexico":

UPDATE Customers 
SET ContactName = 'Juan' 
WHERE Country = 'Mexico'

The selection from the "Customers" table will now look like this:

Update Warning!

UPDATE Customers 
SET ContactName = 'Juan'

The selection from the "Customers" table will now look like this: