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_IdLastNameFirstNameAddressCity
1HansenOlaTimoteivn 10Sandnes
2SvendsonToveBorgvn 23Sandnes
3PettersenKariStorgt 20Stavanger
4NilsenJohanBakken 2Stavanger
5TjessemJakobNissestien 67Sandnes

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_IdLastNameFirstNameAddressCity
1HansenOlaTimoteivn 10Sandnes
2SvendsonToveBorgvn 23Sandnes
3PettersenKariStorgt 20Stavanger
4NilsenJohanBakken 2Stavanger


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!

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