MySQL
- Introduction To MySQL
- MySQL RDBMS
- MySQL SQL
- MySQL SELECT Statement
- MySQL WHERE Clause
- MySQL AND, OR And NOT Operators
- MySQL ORDER BY Keyword
- MySQL INSERT INTO Statement
- MySQL NULL Values
- MySQL UPDATE Statement
- MySQL DELETE Statement
- MySQL LIMIT Clause
- MySQL MIN() And MAX() Functions
- MySQL COUNT(), AVG() And SUM() Functions
- MySQL LIKE Operator
- MySQL Wildcards
- MySQL IN Operator
- MySQL BETWEEN
- MySQL Aliases
- MySQL Joins
- MySQL INNER JOIN Keyword
- MySQL LEFT JOIN Keyword
- MySQL RIGHT JOIN Keyword
- MySQL CROSS JOIN Keyword
- MySQL Self Join
- MySQL UNION Operator
- MySQL GROUP BY Statement
- MySQL HAVING Clause
- MySQL EXISTS Operator
- MySQL ANY And ALL Operators
- MySQL INSERT INTO SELECT Statement
- MySQL CASE Statement
- MySQL NULL Functions
- MySQL Comments
- MySQL Operators
- MySQL CREATE DATABASE Statement
- MySQL DROP DATABASE Statement
- MySQL CREATE TABLE Statement
- MySQL DROP TABLE Statement
- MySQL ALTER TABLE Statement
- MySQL Constraints
- MySQL NOT NULL Constraint
- MySQL UNIQUE Constraint
- MySQL PRIMARY KEY Constraint
- MySQL FOREIGN KEY Constraint
- MySQL CHECK Constraint
- MySQL DEFAULT Constraint
- MySQL CREATE INDEX Statement
- MySQL AUTO INCREMENT Field
- MySQL Working With Dates
- MySQL Views
- MySQL Data Types
- MySQL Functions
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;
SET column1 = value1, column2 = value2, ...
WHERE condition;
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.
UPDATE Customers
SET ContactName = 'Alfred Schmidt', City = 'Frankfurt'
WHERE CustomerID = 1;
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":
UPDATE Customers
SET PostalCode = 00000
WHERE Country = 'Mexico';
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!
UPDATE Customers
SET PostalCode = 00000;
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 |