Описание
1970 E.F. Codd has started a revolution with his paper 'A relational model of data for large shared data banks, Communications of the ACM, Volume 13, Issue 6 (June 1970)' that finally led to the today's omnipresent database query language SQL.
This little app shows some primitive and derived operations with the following information:
* SQL92 and SQL86/89 sample queries,
* the results of the queries and
* appropriate descriptions.
Furthermore the SQL test script that has been used for the calculation of the samples can be displayed.
The app is interesting for the first contact with the database subject and for all who are using SQL86/89 queries for over two decades now and finally want to change to SQL92 also ;)