Flash cards
Review the key moves
What is the main idea behind SQL DELETE Statement?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
DELETE ___ CustomersPut the learning moves in the order that makes the concept easiest to apply.
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 TaquerÃa | 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 deletes the customer "Alfreds Futterkiste" from the "Customers" table:
Example
DELETE FROM Customers
WHERE CustomerName='Alfreds Futterkiste';The selection from 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 TaquerÃa | 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 records in a table, without deleting the table. This means that the table structure, attributes, and indexes will be intact.
Syntax
DELETE FROM table_name ;
The following SQL deletes ALL records 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:
Syntax
DROP TABLE table_name ;
The following SQL drops the entire "Customers" table:
Example
Delete entire "Customers" table:
DROP TABLE Customers;