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SQL DELETE Statement

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The SQL DELETE Statement

The DELETE statement is used to delete existing records in a table.

DELETE Syntax

DELETE FROM table_name WHERE condition;

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

Demo Database

Below is a selection from the Customers table used in the examples:

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
5 Berglunds snabbköp Christina Berglund Berguvsvägen 8 Luleå S-958 22 Sweden

SQL DELETE Example

The following SQL statement deletes the customer "Alfreds Futterkiste" from the "Customers" table:

Example

DELETE FROM Customers WHERE CustomerName='Alfreds Futterkiste';

The "Customers" table will now look like this:

CustomerID CustomerName ContactName Address City PostalCode Country
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
5 Berglunds snabbköp Christina Berglund Berguvsvägen 8 Luleå S-958 22 Sweden

Delete All Records

It is possible to delete all rows in a table without deleting the table. This means that the table structure, attributes, and indexes will be intact:

DELETE FROM table_name;

The following SQL statement deletes all rows in the "Customers" table, without deleting the table:

Example

DELETE FROM Customers;

Delete a Table

To delete the table completely, use the DROP TABLE statement:

Example

Remove the Customers table:

DROP TABLE Customers;

Test Yourself With Exercises

Exercise:

Delete all the records from the Customers table where the Country value is 'Norway'.

 Customers
 Country = 'Norway';

Start the Exercise


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