Tutorials References Exercises Videos Menu
Free Website Get Certified Pro

MySQL Tutorial

MySQL HOME MySQL Intro MySQL RDBMS

MySQL SQL

MySQL SQL MySQL SELECT MySQL WHERE MySQL AND, OR, NOT MySQL ORDER BY MySQL INSERT INTO MySQL NULL Values MySQL UPDATE MySQL DELETE MySQL LIMIT MySQL MIN and MAX MySQL COUNT, AVG, SUM MySQL LIKE MySQL Wildcards MySQL IN MySQL BETWEEN MySQL Aliases MySQL Joins MySQL INNER JOIN MySQL LEFT JOIN MySQL RIGHT JOIN MySQL CROSS JOIN MySQL Self Join MySQL UNION MySQL GROUP BY MySQL HAVING MySQL EXISTS MySQL ANY, ALL MySQL INSERT SELECT MySQL CASE MySQL Null Functions MySQL Comments MySQL Operators

MySQL Database

MySQL Create DB MySQL Drop DB MySQL Create Table MySQL Drop Table MySQL Alter Table MySQL Constraints MySQL Not Null MySQL Unique MySQL Primary Key MySQL Foreign Key MySQL Check MySQL Default MySQL Create Index MySQL Auto Increment MySQL Dates MySQL Views

MySQL References

MySQL Data Types MySQL Functions

MySQL Examples

MySQL Examples MySQL Quiz MySQL Exercises

MySQL UPDATE Statement


The MySQL 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;

Note: Be careful when updating records in a table! Notice the WHERE clause in the UPDATE statement. The WHERE clause specifies which record(s) that should be updated. If you omit the WHERE clause, all records in the table will be updated!


Demo Database

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

CustomerID CustomerName ContactName Address City PostalCode Country
1

Alfreds Futterkiste Maria Anders Obere Str. 57 Berlin 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico
4

Around the Horn Thomas Hardy 120 Hanover Sq. London WA1 1DP UK

UPDATE Table

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

Example

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

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

CustomerID CustomerName ContactName Address City PostalCode Country
1

Alfreds Futterkiste Alfred Schmidt Obere Str. 57 Frankfurt 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico
4

Around the Horn Thomas Hardy 120 Hanover Sq. London WA1 1DP UK


UPDATE Multiple Records

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

The following SQL statement will update the PostalCode to 00000 for all records where country is "Mexico":

Example

UPDATE Customers
SET PostalCode = 00000
WHERE Country = 'Mexico';

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

CustomerID CustomerName ContactName Address City PostalCode Country
1

Alfreds Futterkiste Alfred Schmidt Obere Str. 57 Frankfurt 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 00000 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 00000 Mexico
4

Around the Horn Thomas Hardy 120 Hanover Sq. London WA1 1DP UK

Update Warning!

Be careful when updating records. If you omit the WHERE clause, ALL records will be updated!

Example

UPDATE Customers
SET PostalCode = 00000;

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

CustomerID CustomerName ContactName Address City PostalCode Country
1

Alfreds Futterkiste Alfred Schmidt Obere Str. 57 Frankfurt 00000 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 00000 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 00000 Mexico
4

Around the Horn Thomas Hardy 120 Hanover Sq. London 00000 UK

Test Yourself With Exercises

Exercise:

Update the City column of all records in the Customers table.

 Customers
 City = 'Oslo';

Start the Exercise