QurbanDurrani
asked on
need to understand the relationship amoung tables in a database.
Hi Experts,
I am maintaining a Delphi7 application which workes with tables in a paradox datbase using BDE.
In order to make sure that my application does not violate the referential integrity of a database, my guess is that I need to understand the relationship amoung the tables in the database. Is this correct? and if yes, How do you achieve that in a paradox database?
I am maintaining a Delphi7 application which workes with tables in a paradox datbase using BDE.
In order to make sure that my application does not violate the referential integrity of a database, my guess is that I need to understand the relationship amoung the tables in the database. Is this correct? and if yes, How do you achieve that in a paradox database?
Table relationships (database relationships) can be related in three ways:
One-to-One, One-to-Many and Many-to-Many.
I usualy write my answers but since there are many well documented pages about this topic, I am posting his link.
http://www.informit.com/articles/article.aspx?p=31475&seqNum=4
I hope it will guide you in right direction.
One-to-One, One-to-Many and Many-to-Many.
I usualy write my answers but since there are many well documented pages about this topic, I am posting his link.
http://www.informit.com/articles/article.aspx?p=31475&seqNum=4
I hope it will guide you in right direction.
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER CERTIFIED SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
Thank you so much to all of you for your very informative answers, even though I did not state my question very clearly.
I use paradox and Database desktop. Is there a way in Database Desktop to find out the relationships amoung the tables in the database. For example if table1 is a master to table2 which is a master to table3 which is a master to table4 and table2 is also a master to table7. and so on. Is there a way in Database desktop to find out these relationships, other that just looking at all the table for hours and still miss some relationships.
Thanks again for all the help.
I use paradox and Database desktop. Is there a way in Database Desktop to find out the relationships amoung the tables in the database. For example if table1 is a master to table2 which is a master to table3 which is a master to table4 and table2 is also a master to table7. and so on. Is there a way in Database desktop to find out these relationships, other that just looking at all the table for hours and still miss some relationships.
Thanks again for all the help.
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
The relations do exist. Now if that is not the same as being defined, that how do I find out if they are defined?
How do I get the Entity-Relation-Diagramm?
Thanks
How do I get the Entity-Relation-Diagramm?
Thanks
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
Thanks guys for the very informative answers.
even in paradox you can define releationships between tables,
which are watched by the paradox-engine,
so you do not need to care about the relations within your delphi-app
(you may get an exception if you are about to avoid the defined relation)
so what is the question?
meikl ;-)