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) that 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 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 |
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:
or:
DELETE * FROM table_name;
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