SQL exercises
Language 
March 29, 00:31 MSK
Login:

Password:

forgot password?
Registration

Personal page
Developers & Thanks
For employers
References
Feedback
Support SQL-EX.RU



Feedback

Author Comment            page 1 2 [3] 4
Evgeniya Smolkina,
Sibirtelecom Ltd. (Novokuznetsk), engineer-programmer,
05/05/2009
Though at job basically I work with Oracle, this site has very much helped me with my work; that I would write a long time earlier, now, having acquired skills, turns out almost instantly.
Try to convince, not one I am grateful for creation such talently developed and at a serious level of an accompanied resource, analogues today did not meet at the web. Any textbook will not give such effect, as a school on SQL-EX.RU. A theory goes without saying, but in a life is necessary practice and an exchange of experience, as we receive on SQL-EX.RU all.
Many thanks to Sergey Moiseenko and Dmitry Valuev for their help and patience, I appreciate to Roman Golubin, Pavel Vojnov and everyone, who shared their scripts and a problem-solving procedures on forums, to all enthusiasts, who has created this resource and has made its such necessary and effective.
I want such resources both on Oracle, and on development framework, and... And then we shall prove to everything, that our Russian educational systems on IT and at all is super and best!)) More power to your elbow in the further development!
Zotov Pavel,
Technical Center "Kuntsevo" (Moscow, www.kuntsevo.com), database programmer,
10/18/2008
A site gave me in oftentimes more than I could present. It compelled to apply correct skills of thought, instilled a notorious paradigm "to solve the task in terms of set". I am sure that it will be never given neither 2- or 3-week courses neither huge folio nor even joint work in one room with some sql-guru. All of it was got for the relatively small interval of time, approximately half-year. And free of charge: I don't want to take into account small certificates payment (furthermore, it was quite voluntarily). I suppose that such level of knowledge can be got only in institute of higher education.
I want to thank developers and many participants of site for the presented tasks. No doubt that for development of many exercises considerable time was required (especially for filling of verification base with different combinations data). Many tasks are simply beautiful and extraordinary so decision of them using non-procedural language (SQL) compels it is pleasant to be surprised.
It is impossible not to mark carefully thought out of placing of tasks in a general list, smooth growth of their general level of complication. At the same time, after couple of difficult exercises more easy one follows necessarily. Therefore no fatigue accumulates and process of decision does not become tiresome business only for the sake of receipt of certificate. Another thing: the developers of site keep their own word. They indeed do not give up "sinking" and always give a chance to solve a task providing you with useful hints after some time. With regard to the total amount of participants (for today almost 20,000), it is impossible not to delight in patience of developers, accompanying this remarkable resource and helping all of participants.
Fedotova Ekaterina,
eHouse Internet Holding (www.ehouseholding.ru), database programmer,
04/09/2008
I am glad to inform you that I have got my certificate today.
Thanks a lot for your site! I have not found anything of the kind on the net before. The source has proved to be highly useful for me, especially because I have not got the kind of education needed in my job, and there is no right person to instruct me around.
The solution of the problems and the study of forum discussions have proved to be a valuable experience that I successfully use in my work (even though I use Oracle 7).
As soon as I have time for it, I am going to continue doing your exercises.
Dmitry V. Borisenkov,
Relex Inc., Voronezh (Russia), Chief Specialist,
03/22/2008
If you are developing database software or studying computer sciences, don't miss this site! Task solving contest being held here is an unique opportunity to test and improve your skills in writing complex SQL queries. You can compete with other programmers both in speed of writing queries and speed of written queries execution by DBMS. In case of any troubles with task solving site admins will give you a lot helpful explanations. But there is one danger: you can become addicted to this site and put off your job responsibilities spending many hours solving contest tasks ;-)
Bhav Tailor,
07-03-2008
I am a database manager from England. I started my job 6 months ago and have found that your site is really helpfull. I think there needs to be more exposure for people who are struggling with SQL. This indeed is the most educational SQL tool I have ever used. Many Thanks.
Renat Muhametshin,
Programmer of IT department at administration of Pervouralsk.
07-14-2007
Here have been passed almost 6 improbable months of solving the tasks on excellent training resource sql-ex.ru. It is teaching not only a theory (for beginners in SQL whom I was myself), but also at once on all of 1000 percent is perfecting practice of a writing of queries and understanding of the scheme of a database.
It is possible to tell that after solving first hundred of exercises (if you are beginner in SQL), you feel yourself as expert and do not distract yourself any more for finding the information on language functions for work with character strings and dates what couldn't be said even after the decision of 67 exercises :-)). However there is a type of exercises which caused much difficulties for me, these are problems on those or other sequences, and these are just near of 120 exercise (surely, there is 92th also, but nevertheless...), so it is necessary to pass through to the end.
However, there are few lacks (I'll notice that they are not defects of the site, but these are to be wanted parts). It is not enough exercises on DML - syntax is forgotten, though there is certainly a tutorial. Also, it would be merely super if the visible database has been filled by data considering all those conditions that are constructed in checking database - certainly, developers will be distracted less. As for common "problem" of understanding the conditions of tasks, here as they say: you will not please for anyone ;-). However discussions at forums, and also letters to developers about misunderstandings of task formulations could enforce some changes.
Generally, many thanks to all who has made all this. Experience you receive here is huge!!! and what is important!!!!!! FREE OF CHARGE. Separate thank Serge I and Fiolent for their help at the solving the exercises.
saberhagen,
06-09-2006
Wow! This happened! Today I was invited to an employment interview to an office (not software developers, but oilmen). Mainly, there were required T-SQL skills - that is, the heads say what info they want, the analytic finds the input parameters and gives a task to create SP to the programmer, and the programmer forms a query and saves it as a SP object, the heads append to the SP through a separate software and enjoy the grid in Excel. Obviously, the SP remains forever - just in case somebody else needs this report.
As I was told later, there had been 15 tasks on T-SQL, by increasing difficulty. Well, I thought I got stuck - it's a waste of an hour. Luckily, after completing the 1st task I accidentally said that at www.sql-ex.ru such tasks are in the top 10. I was asked - how far did I get there? I answered that I almost finished all (in fact, 7 remain before the end). They requested for the sql-ex certificate - fortunately, I had copies of all my certificates. They checked the certificate number on www.sql-ex.ru and said they have no more questions on T-SQL and moved on to the next topics - administrating and VB programming.
I'm glad! I also have MS SQL certificates from Microsoft (administrating and programming), but no one even glanced on them and I was examined by the whole program.
That's it! And you say - "not rated, not rated"… it's highly rated!
K.V. Kholin,
Deputy director of Novosibirsky regional voluntary fund of the Olympic champion in Graeco-Roman wrestling Alexander Karelin "Karelin fund", Novosibirsk, Russia
06-01-2006
On the occasion of completing the AR certificate requirements, I voice my gratitude to Serge I for the contribution to my education (a year before I even didn't know what these beautiful SQL letters mean). I consider your resource as the best educational one (with all my respect to courses by Kuznetsov S.D.). I wish you all the best, and further development to the project. I express my thanks to the developers' team. Great thanks to all authors of the tasks and all participants who published their results on the forum.
Special thanks to Roman S. Golubin for your style of highly efficient solutions.
My rating of tasks from #1 to #121 (those which I enjoyed or gained life experience while finding solutions):
1st place - №60 by Serge I
2nd - №72 by pаparome
3rd - №110 by Snowbear
4th - №121 by ZrenBy
Arik Frenkental,
DBA from Israel,
05-10-2006
To Serge and the rest of the team.
I would like to express my appreciation to the idea of your site and to its implementation. Finally an interesting, enjoying and a challenging SQL site. The Ratings system adds to the interest.
I hope to make it to the final exercises to earn your full certification.
Good luck to you all.
Laric,
04-30-2006
Dear developers!
I'm a programmer for 25 years already. But my profession is very specific (war industry). Another hard time came and the company stopped paying wage. I took a look around and realized that I have a terrible prospect: a woman over 45 is not rated by the employers, while our specialization's not needed at all. I gathered information on the vacancies and found out that database and SQL skills are required. It's easy to study the databases on the Access level, but then…
And then I found your site, just after another failed employment interview. I was very lucky.
Of course, I didn't cope with all the materials but even that was enough to find a job with salary on 70 % above, than was.
Period of probation for me was shortened from 2 months to 2 weeks. Now I'm officially registered to a permanent job.
THANK YOU VERY-VERY MUCH!!!
M. Vasanthakumar,
02-02-2006
It's a great place to learn and practice SQL on web. Hats off to the Team. Thanking you.
Heiretdinoff Renat Valiullovich,
SKB-Kontur Inc., Ekaterinburg, Russia
01-13-2006
I greet the developers and organizersof this project. I express my thanks and respect for creating such a useful site and for the free access to it. My own wish is to ask somehow the forum people to stop publishing solutions that had been posted already or at least to give a link to published queries. It's more desirable to see unordinary ideas of completing tasks, to analyze their efficiency, to find the best one… But when you look at 5 forum pages (for example, #25) - you get sick from knowing there are no more than 3 principally different variants that are worth considering.
And another request: it would be great to have an ability to format the text with the common tabulation button in the query editor, though I don't know if it's possible to realize this. Thanks beforehand.
Author Comment            page 1 2 [3] 4



Home
Week news
Certification
SQL exercises
Forums
Ratings
HELP
Performance
Profile
References
Copyright SQL-EX © 2002-2024. All rights reserved.
contact