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Thanks David,
I am going to be doing some conversions and needed to understand this setting so as to avoid time consuming and unnecessary "glitch repairs". I understand the syntax of the form property much better now. I think I can predict and select the appropriate one-to-many/many-to-many setting in most normal situations (which was my primary need) and can test out the results in the rest as required.
Thanks for your help,
Michael Michael Moser EXAQ Micro Services www.exaq.com Phone: 916-966-8313 Fax: 916-966-8313 >> Not necessarily. I BELIEVE - but I haven't tested this, that if you had 3 >> tables, Table 1 in one to many to Table 2 and Table 1 in one to many >> with Table 3, that this would be ONE to MANY MANY to MANY means more >> than one level of >> relationships Table 1 one to many with Table 2 Table 2 one to many with >> Table 3 David David Blocker >> [EMAIL PROTECTED] >> 781-784-1919 >> Fax: 781-784-1860 >> Cell: 339-206-0261 ----- Original Message ----- From: Michael Moser To: >> RBG7-L Mailing List Sent: Saturday, March 12, 2005 3:22 PM Subject: >> [RBG7-L] - Re: When is a one to many form appropriate wtih 3 tables >> Hi David, Thank you, that makes sense. Just to clarify then in this >> context, in any normalized data schema situation any form with more than >> 2 tables is going to be a many-to-many form in R:Base 7. This is true >> because 3 or more tables will always >> have "many (more than one) one-to-many" relationships. yes? Thanks, >> Michael >> Michael Moser >> EXAQ Micro Services >> www.exaq.com >> Phone: 916-966-8313 >> Fax: 916-966-8313 >> >> Michael In 7.x, the term "Many to Many" on the form properties screen >> is >> >> not used in the classical relational database meaning. You have MULTIPLE >> >> >> one to many relationships and so in 7.x you should use the "Many to >> >> Many" setting (it really should read >> >> "Multiple One to Many" but who's quibbling!) David Blocker >> >> [EMAIL PROTECTED] >> >> 781-784-1919 >> >> Fax: 781-784-1860 >> >> Cell: 339-206-0261 ----- Original Message ----- From: Michael Moser To: >> > >> ! > RBG7-L Mailing List Sent: Saturday, March 12, 2005 11:38 AM >> Subject: >> >> [RBG7-L] - When is a one to many form appropriate wtih 3 tables >> >> Hi All, >> >> I just joined the list server so this topic may have been addressed in >> >> >> the past. If so I beg your indulgence one more time... I am trying to >> >> >> understand when to use the one-to-many setting and when to use the >> >> many-to-many setting in the form properties >> >> when using R:Base 7.1 forms With two tables, A and B, with a >> one-to-many >> >> (<) relationship between the two (A<B), the form properties are set to >> >> >> one-to-many and the form works correctly. How ever if three tables are >> >> >> used (A, B, and C) such that: >> >> ! Table A has a Primary Key Table B has a Primary Key and a! Foreign Key >> to A >> >> Table C has a Primary Key and a Foreign Key to B Table A and Table C have >> >> >> no common fields Thus creating a one-to-many relationship between A and >> >> >> B, and a one-to-many >> >> relationship between B and C (A<B<C). If a view AB was created from >> >> tab |
- [RBG7-L] - Re: When is a one to many form appropriate with 3... Michael Moser
