This course uses the awarded SQL-Trainer facility for practicing SQL queries and SQL update operations. SQL-Trainer provides a web user interface for carrying out operations on an example database. This course uses a kitchen furniture database for practicing. Tables are named in English. You may inspect the structure of the database also as a graphical schema diagram. Print it and use it in building the queries. You get the description of the database also thru the trainig software. SQL-Trainer presents you the tasks to be solved.
To start the SQL-Trainer fill the login form at the end of this page. Deadlines are defined in the course home page.
You may pick up any user id. The first time you connect to the Trainer (with a new id) you reach the registration page without giving a password (if not, then the id is already in use). You should define a password. Later on you must use this password. Personal number is needed for connecting the training results to course bookkeeping and crediting.
If you have forgotten your password, contact the instructor.
Tasks have been split into groups each with a deadline. You get credits if you are able to solve the task before the deadline. SQL-Trainer shows which tasks you have already solved. It does not, however, show how many tasks have brought in credits.
You may try to solve a task as many times as you like. The number of tries does not affect the credits. The first task 'free practicing' is intented for trying your own queries. There are less checks done for that task.
If you get Internal server error -messages, the reason may be
Please, report these errors to laine@cs.helsinki.fi.
If the program just seems to do nothing after you have delivered a query, your query is probably very large, i.e. it retrieves a lot of rows. This may be due to missing join conditions. Although the example tables are small, you might get very large results, if you forget the join conditions. Currently there are no means to cancel a query. If you get into this situation, just wait and do not try again before you have considered changing the query.
Date literals should be given in ANSI standard format (DATE 'yyyy-mm-dd'), for example DATE '2006-03-15'. Another way to give a date constant is to use Oracle's to_date function, for example to_date('15.3.2006','dd.mm.yyyy')
Some error messages are given by the dbms. They contain an error number in the beginning. Oracle manual on error messages may give some advise on how to find the error. You may also give the error code as the search key for Google and get explanations on the error.
You may build your queries by starting with a simple query and the adding tables and conditions to obtain the final query.
There are now two start forms below, one for the primary system and the other for the backup system. They both run the same software and use the same database.
First connect: Pick any user id (user accout, lastname, nicname,...), no password needed
If the primary server does not work or just to balance load: