Most of you completed this assignment with few or no problems so there should be a great deal to say. However:
Next Assignment
- A reminder that for A2b I expecting you to use real sensors that you’ll research using catalogues or other sources. It’s OK if not every field has data – that will show how hard it can be to truly characterize a sensor from the published information.
This Assignment
- Some of you deleted a record in a table and then added it back, expecting to be able to assign the old ID number. That doesn’t work: When Access says “unique” it means unique for all time for a given table. It actually is a “feature not a bug.” If you were able to create an ID that had already been used you might inadvertently link to records you hadn’t intended in other tables. It does show that you want to be careful deleting records – the general rule is: Don’t. Most database designers hide the ID and key from users to avoid this confusion.
- Some of you wondered why have forms rather than just enter info into queries or tables. The answer is that you can make forms very “pretty” and can also associate “logic” with them to do interesting things.
- A few of you struck out on your own rather than following the videos exactly. Congratulations! Unfortunately that exposed you to the more complex side of Access such as multiple versions of a table being linked – that can be very helpful, but it’s quite confusing.
- Finally, only one person reported playing with the templates. I recommend it. Some of them are extremely well developed. You may find them hard to understand initially since they use lots of features we haven’t touched, but they do neat things and can be modified to suit your needs much more rapidly than starting from scratch.
Jim Mitchell
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