Slide 7.11: SQL update statement
Slide 7.13: Embedding SQL in ASP.NET
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SQL Delete and Drop Statements

The DELETE statement is used to delete rows in a table. Notice the where clause in the delete syntax. The where clause specifies which records that should be deleted. If you omit the where clause, all records will be deleted!

Assume the Persons table is given below: 
 DELETE FROM  table_name
   WHERE  column_name = some_value

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 Rasmussen Nina Stien 12 Stavanger 

 DELETE FROM  Persons  WHERE  LastName = 'Rasmussen';
 DELETE FROM  Persons;
P_Id LastName FirstName Address City
1 Hansen Ola Timoteivn 10 Sandnes
2 Svendson Tove Borgvn 23 Sandnes
3 Pettersen Kari Storgt 20 Stavanger
P_Id LastName FirstName Address City

The DROP TABLE command is to delete a table (the table structure, attributes, and indexes will also be deleted): 
 DROP  TABLE  table_name


Demonstration
The following is an SQL test area from W3Schools, which uses the well-known Northwind sample database and the tables are for read only.
For security reasons, the following demonstration may only work in Chrome.

SQL Statement:

Edit the SQL statement and click     to see the result, or    

Result:

Click “Run SQL” to execute the SQL statement above.
W3Schools has created an SQL database in your browser.
The menu to the right displays the database, and will reflect any changes.
Feel free to experiment with any SQL statement.
You can restore the database at any time.
The Database includes:
The Database includes:

TablenamesRecords
Customers91
Categories8
Employees10
OrderDetails518
Orders196
Products77
Shippers3
Suppliers29