SQL | Archived exercise | Delete adult and betting sites, then roll back

This exercise is provided to allow potential course delegates to choose the correct Wise Owl Microsoft training course, and may not be reproduced in whole or in part in any format without the prior written consent of Wise Owl.

Software ==> SQL  (198 exercises)
Version ==> Any version of SQL Server
Topic ==> Archived  (70 exercises)
Level ==> Average difficulty
Subject ==> SQL training
Before you can do this exercise, you'll need to download and unzip this file (if you have any problems doing this, click here for help).

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If you haven't already done so, run the stored procedure in the above folder to generate a database of the world's leading websites.

This database contains a table called Data_at_14_Jan_2010, which contains the source data for the other tables:

SQL exercise - Transactions (image 1)

We're going to remove all BETTING and ADULT sites, such as the one shown selected

Write a query which:

  • Begins a transaction
  • Within this transaction, deletes all rows from the above table where the Category column is Betting or Adult
  • Stores how many rows are left in the table in an integer variable
  • Rolls back the transaction
  • Stores how many rows are in the table after this roll back (in a second integer variable)
  • Displays the final figures

Your query should display output similar to this, when run:

SQL exercise - Transactions (image 2)

The transaction (if not rolled back) would have deleted 9 sites

Optionally, save this code as Delete sites then roll back.sql, then close it down.

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.
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