Exercise: Update table, then undo changes with a transaction

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The answer to the exercise will be included and explained if you attend the course listed below!

Category ==> SQL  (192 exercises)
Topic ==> Transactions  (4 exercises)
Level ==> Average difficulty
Course ==> Advanced SQL
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). Once you've done this:
  1. Go into SQL Server Management Studio;
  2. Open the SQL file you've just unzipped (you can press CTRL + O to do this); then
  3. Execute this script.

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Use an UPDATE statement on the tblCountry table to set the CountryName column to include the words (My Country) next to the country you call home:

Update Transaction Commit Rollback

Just saying....

Now change the code to add (Holiday destination) to the other countries within a transaction. After running the update statement:

  • roll back the transaction if 1 + 1 = 2 (it does); or
  • commit it otherwise.

When you run this query, nothing should change:

Begin Transaction Commit Rollback

When excluding your country remember to use wild cards to account for the changed name!

Change the condition to test whether 1 + 1 = 3 (it doesn't), and rerun it.  Check that the extra text has been added:

Commit transaction and update table

If you have nothing better to do, change Holiday to Visited for countries you've been to.

Finally, as a bit of housekeeping please reset the country names by running this query:

-- reset country names

UPDATE tblCountry

SET CountryName = REPLACE(CountryName,

' (Holiday Destination)','')

-- check this worked

SELECT * FROM tblCountry

If you could also manually reset the name of your home country back to its former glory, that would be good!  Thanking you ...

Optionally save this as Stake your claims.sql, and then close it down.

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