Exercises of a learning stage are available now for several DBMS. MS SQL Server, MySQL, PostgreSQL are currently supported at the site.
11/13/2010
Use of the common table expressions (CTE) for the solution of exercises on DML and for the majority of rating-stage's exercises on SELECT is allowed now.
07/06/2010
Searching and bookmarks service have appeared in the site forum.
01/30/2010
The new stage named "Puzzles" is implemented. Exercises of this stage begin with No.251 and are accessible to participants of 3rd stage.
The points earned on solving of these exercises do not give a contribution to 3-rd stage, but are included into the total number of points of rating exercises.
07/01/2009
New service - Modelling of data - has been launched. Service allows to add the data into the database for exercises of 2/3 stages and to compare the results on these data of test solution with own query.
Exercises voting is a new service that appeared on the site.
You can estimate any task of second/third stage by 10-point scale now.
03/22/2008
On the page of Rating of second-stage exercises the list of those who have begun the solving an exercise can be seen.
Similar functionality was done on statistics' page . You can get list of professionals in a given geographical location.
Updating of the forum. New features:
- Editing and removal of messages;
- A prompt reply with citing.
09/09/2006
Third testing stage was started with exercise #139
07/09/2006
Feedback page of visitors and participants of rating system about the site is added.
05/13/2006
The page with the chart of the results shown by participants while solving the exercises on the second stage (SELECT) is added: chart.php . It is possible to compare your results with the results of other participants.
04/08/2006
The book "SQL. Problems and solutions" (in Russian), which is analyzing the characteristic mistakes admitted at the solution of the first stage exercises on the site, was published in Peter Publishing Company. .
The new resource is opened.
Besides other, the analysis of typical mistakes is published there for the first stage exercises.
12/09/2005
Checking exercises on independent data is realized,
i.e. for each exercise now there is an opportunity to create own checking database.
It allows to carry out check of correctness of the solutions more effectively.
