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On 22/02/13 15:34, Philip Hudson wrote:
I think you've got the wrong end of the stick here. Simon is recommending client-server and a DB "Management System" (DBMS) over stand-alone/embedded and file-based; *not* CLI over GUI. Calculated fields are only a feature in standalone systems.
Right. And as I understand it both Kexi and OO Base are meant to be the Linux equivalent of Access. So they are meant to be stand alone systems. Yet neither one has managed to include calculated fields as simply as Paradox was doing years ago.
In SQL-based
systems they are implemented using the SQL query language, offering a great deal more power, flexibility, dynamism and customization. To get the equivalent (actually much more powerful) of a calculated field most modern SQL DBMSes offer what are called "views" -- essentially tables that are the output of queries on one or more underlying tables (and/or views). Calculated fields are actually a Bad Thing in large-scale database design in that they break what is called "normalization", a series of steps and tests for making sure you duplicate (ideally) nothing.
I do understand the idea of normalisation.
Paradox is a relational database with indexes. (And forms and queries and reports and a specially written scripting language all in the one package). Obviously it was not suitable for everything and the Mysql, Mariadb system is needed too.Conceptually, you need to be separating two areas of design that are unified (to some advantage, but with trade-offs) in Paradox etc: schema design (tables, indexes, etc) and form/application design (quite a different topic, with very different priorities).
Yes, I do understand the above. And I understand the concept of 'views'. Again I have not made myself clear. I am not saying there is anything wrong with SQL based systems, as described above. Of course they are needed. I am asking for just one stand alone system as good as Paradox was years ago *as well*. Is that too much? Isn't there a need for both?I've never coded to PG but I know MySQL now offers views, and I'm sure I'd have seen something to the effect that PG was behind if it didn't, so I assume PG also offers them.
Neil -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/listfaq