SQL DELETE Statement

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# SQL DELETE Statement

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

## The DELETE Statement

The DELETE statement is used to delete rows in a table.

### SQL DELETE Syntax

    DELETE FROM table_name
    WHERE some_column=some_value

Note: Notice the WHERE clause in the DELETE syntax. The WHERE clause specifies which record or records that should be deleted. If you omit the WHERE clause, all records will be deleted!

## SQL DELETE Example

The "Persons" table:

P_Id | LastName | FirstName | Address | City
--- | --- | --- | --- | ---
1 | Hansen | Ola | Timoteivn 10 | Sandnes
2 | Svendson | Tove | Borgvn 23 | Sandnes
3 | Pettersen | Kari | Storgt 20 | Stavanger
4 | Nilsen | Johan | Bakken 2 | Stavanger
5 | Tjessem | Jakob | Nissestien 67 | Sandnes

Now we want to delete the person "Tjessem, Jakob" in the "Persons" table.

We use the following SQL statement:

    DELETE FROM Persons
    WHERE LastName='Tjessem' AND FirstName='Jakob'

The "Persons" table will now look like this:

P_Id | LastName | FirstName | Address | City
--- | --- | --- | --- | ---
1 | Hansen | Ola | Timoteivn 10 | Sandnes
2 | Svendson | Tove | Borgvn 23 | Sandnes
3 | Pettersen | Kari | Storgt 20 | Stavanger
4 | Nilsen | Johan | Bakken 2 | Stavanger

## Delete All Rows

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

    or

    DELETE * FROM table_name

Note: Be very careful when deleting records. You cannot undo this statement!

From http://www.w3schools.com (Copyright Refsnes Data)