Re: [libreoffice-users] definition of flat/relational database

On 03/03/2013 10:09 AM, John R. Sowden wrote:
> Why do the Libreoffice powers that be define dbase/xbase as  a flat 
> file database, not a relational database. The below definitions from 
> the Base Intro documentation demonstrate what I am saying:
>
> *Flat databases*
>
> A flat database contains one or more tables, each containing one or 
> more fields. Each table is completely independent of all the other 
> tables in the database. For example, I have an address database with 
> seven tables in it. One has my family's contacts, another has my 
> business contacts, and another has my wife's family contacts. While 
> some contacts are contained in more than one table, different tables 
> may not have the same information about the same person.
>
> dBase is a flat database program. LibreOffice and several database 
> programs can also create flat databases.
>
> *Relational databases*
>
> Relational databases contain one or more tables with one or more 
> relationships; each relaltionship is defined by a pair of fields. One 
> field of each pair belongs to one table and the second field belongs 
> to the same or a different table. Where relationships exist between 
> fields in the same or different tables, a flat database could still be 
> used, but it provides no mechanism for defining the relationship. 
> Instead the same data must be entered in both fields, making data 
> entry errors more likely. A well designed relational database requires 
> the data to be entered only once, reducing possible errors.
>
> dbase is a relational database per the above definition.  I link 2 
> tables with 1 field so I can refer to data in the second database so 
> data does not have to bbe entered multiple times.  In our alarm 
> monitoring station, when a police dept. changes its phone number, we 
> change 1 field in 1 database.  Hundreds of subscriber records refer to 
> that field to populate the data screen.  It seems that LO ptb either 
> have a problem with dbase/xbase, or they are (were) uninformed of the 
> facts.
>
> John Sowden
> (been programming in dBase II (under cp/m), Foxbase, Foxpro (under 
> DOS) since 1981)
     The beginning of this thread was: "Why do the Libreoffice powers 
that be define dbase/xbase as  a flat file database, not a relational 
database." As the author of the definitions that John quoted at the top, 
I am part of the powers that be in LO when it comes to these definition 
. Early in this thread I asked for suggestions as to what the quoted 
definitions should be. Sorry folks, but I do not see any suggestions 
that is good enough to replace what has already been written. What I 
have written may not be as good as it should be. Neither has anyone 
produced anything to replace what I have written. When someone suggests 
much better definitions, they will be replaced.
     I'm still don't understand what the structure of dBase2 is. How 
can you use two or more tables in a query for example using this 
database engine?
     And for those who have begun discussion what database engines 
might be better of a person's use, please create a new thread so others 
searching the archives can more quickly find the comments about 
different databases. They are not likely to think that this thread would 
contain this information.

--Dan

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