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  1. B

    Distributed Database

    That's not a distributed database; it's just file-sharing by email. It sounds like a rather user-unfriendly solution with plenty of pitfalls. Why can't you just create some web-pages that they fill in via a browser? Not sure why you'd need to use PDF technology to do that.
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    database structure

    Slimjen, Autonumber is not the solution. The problem implicit in your question is this: what to use as an identifier for customers without an SSN? That's a business question, not a technical one and it isn't solved by adding a surrogate key. Surrogate keys are usually not exposed to business...
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    Should I avoid 1-to-1 relationships?

    Pretty much every other DBMS gives you that kind of help, and does a far far better job of it than Access. Except that the queries it produces will in many cases use Jet/ACE specific dialect of SQL that is incompatible with everyone else. All SQL DBMS have some proprietary elements but no other...
  4. B

    Should I avoid 1-to-1 relationships?

    I wasn't actually criticising Access in general. The "crutch" I was referring to was simply the Access feature which makes a "relationship" become a default for the joining condition when you design a query in the Access UI. That feature is unnecessary and can be ignored if you write your own...
  5. B

    Should I avoid 1-to-1 relationships?

    Certainly not so for anyone even moderately competent at SQL. And a person so inexperienced as to "need" such a crutch probably ought not to be designing a database. Inexperienced developers are better off using other tools anyway.
  6. B

    Should I avoid 1-to-1 relationships?

    Now I get what you are saying. To be clear, I was talking about data integrity constraints whereas you are referring to the weird UI "features" that in Access also go under the name of "relationships" - an irrelevance really. The default join clause used in the Access UI has absolutely nothing...
  7. B

    Should I avoid 1-to-1 relationships?

    The essential point about implementing 1-1 or 1-0/1 cardinality accurately is that you have a uniqueness constraint on the referencing foreign key. If you implement such a uniqueness constraint than there can never be more than one referencing row, thus 1-0/1. It is only a 1-many relationship if...
  8. B

    MS Access vs .NET

    This seems like an oddly old-fashioned view of a developer's job (the title "programmer" being relatively unusual these days). Modern development practices tend to favour cross-functional teams where developers most definitely are involved in design, testing and working closely with users over...
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    MS Access vs .NET

    If your goal is to maximise your appeal to potential employers now and in the forseeable future then get some experience on one of the major development platforms, e.g. .NET or Java EE. In the .NET space VB.NET comes very much second to C#. If you've decided to make the move to .NET then C# is...
  10. B

    Should I avoid 1-to-1 relationships?

    emorris, Your design sounds perfectly reasonable. When you implement a foreign key constraint between two tables that share the same key then that's really one-to-zero/one (sometimes called Z-cardinality) and not strictly one-to-one. A strict one-to-one relationship constraint between two...
  11. B

    er diagram

    There are numerous tools you can use to create ER diagrams and most of them will reverse-engineer an existing database and document it for you. There is a list of modelling tools here: http://www.databaseanswers.org/modelling_tools.htm Avoid the Access "Relationships" window. It doesn't create...
  12. B

    Relationships and referential integrity in linked/imported data DB's

    Clearly it would be better not to use Jet at all. Get SQL Server (you can download Express Edition for free) or any other SQL DBMS. You can of course still use Access on top of the database. Also I don't understand why you are importing via Excel. It ought to be easier to go direct into your...
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    Is Microsoft Access a 'proper' database?

    Access self-evidently is not a "database". It is an application development tool. As an application development tool it's never going to compete with more mainstream RAD tools based on .net or Java, say, but Access fits its own niche quite nicely. The main drawbacks for most people are that it...
  14. B

    Same primary key in one-to-one relationships?

    Such a relationship is actually 1 to 0/1 and not strictly 1 to 1 because the row on the referencing side (where the foreign key sits) is optional. 1-1 is usually best implemented in one table but in practice 1-0/1 is much more common and it's a perfectly sensible thing to implement a 1-0/1...
  15. B

    See Diagram - Best Plan for Review - Big Logic Based Reports

    Metadata is "data about data", i.e. data that describes and configures aspects of the structure, behaviour or integrity rules of other data. Examples could be data that defines data types, constraints, dependencies or mapping rules. The distinction between data and metadata is necessarily...
  16. B

    unambiguous identification of file

    Use a source control system or content management system? In principle I think it's possible to use the NTFS journalling features to track changes to files but using a content management system of some kind is probably easier and would give you a richer set of features.
  17. B

    Medication data - complex grid

    Are you familiar with the healthcare metadata standards in use in your client's jurisdiction/organisation? In many places the use of metadata standards is a legal/regulatory requirement for healthcare applications. Even if they aren't mandatory in your case, the relevant industry standards would...
  18. B

    Table Setup

    I think I nearly fell off my chair when I read that! Possibly what Pat means is this: there is a certain subset of Oracle features that do have equivalent or similar support in the Jet/ACE world and the differences across platfoms in those common features alone are probably not too difficult to...
  19. B

    Delete duplicates, retain unique records

    Nobody has yet mentioned what might be the most important part of the solution: add a uniqueness constraint to prevent any more duplicate data in future. In other words don't just mop the floor; fix the leaking pipe as well!
  20. B

    Validation Rules with Multiple Criterias

    That's an important issue: data integrity in the application vs data integrity in the database itself. Putting data integrity rules into the database usually has many advantages over doing it in the application. Putting data integrity in the database means you have just one place to maintain...
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