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Database tables
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28/10/2004 14:48:49
 
 
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28/10/2004 14:20:05
Information générale
Forum:
Visual FoxPro
Catégorie:
Autre
Titre:
Versions des environnements
Visual FoxPro:
VFP 6
OS:
Windows XP
Database:
Visual FoxPro
Divers
Thread ID:
00955421
Message ID:
00955444
Vues:
11
>What is the difference between free tables and those tables that are included in a database? What are the advantages and disadvantages of each?
>

Not really such a quick question, but let me provide the beginnings of a response.

Physically, the difference is that a table in a database carries within it a link to the database, so that when you open the table, it opens the database as well.

Your second question is really the important one. Why use free tables? Why use the database container?

Free tables have the advantage of being highly portable and, if you use Fox2x tables, highly backward compatible.

Putting tables in a database gives you a number of capabilities that free tables don't offer. You can set up field-level and row-level rules to keep bad data out. You can set up default values for fields. You can set up triggers that fire when you add, change and delete records; among other things, you can use triggers to enforce referential integrity between tables (so that, for example, you can't delete a customer if you have orders on file for that customer).

This topic in the FoxPro Wiki should give you more information: http://fox.wikis.com/wc.dll?Wiki~FreeTable~VFP

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