If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
How do I design a database based on the information that will be stored? - Copy of Tables and hirearchies.zip (0/1)
Hi I am trying to learn how to design a relational database. I have
designed one database in access 97 but it was a flat database file since I didn't know how to do relational ones and needed it done quick. I am using access 2002 to design this one but it will be read from a visual basic program and displayed in an MSHFlexGrid. Attached is an excell file (trimmed down and zipped) with the tables that I need to store, I need to know how to decide how they should be formatted in a database. Some of the tables have colums that are not in other columns. Do I make a database table for each of the tables? Do I make one big table that has all the same colums in it and only make new tables for the colums that are not in all of the tables? Is there some other/better way? How do I know what/how to link the tables so that they are efficient. I figure there is probably alot to consider so I am not asking for the absolute best/fastest/efficient way, just a basic start on how to do it. Also I am not looking to just have someone make the file for me so I ask that if you tell me how to format it to please explaine how/why you are saying to format it that way. The particular file for this data is not realy important I am looking to learn how to make a relational db. Any and all help is appreciated. Thanks in advance! Jim |
#2
|
|||
|
|||
How do I design a database based on the information that will be stored? - Copy of Tables and hirearchies.zip (0/1)
Jim
Shut off your computer and pick up paper and pencil. Forget how you have set up "tables" in Excel -- the 'tool' constrains how you can organize the data, and hence, your thinking. What entities are you working with? For example, if you are working with students, you might have the following entities: Person Course Person-Taking-Course (i.e., a "student") Jot those down. Now consider what pieces of information you will need about those entities. For example, the first and last names of persons, the subject matter of a course, the start-date of "Person-Taking-Course", and maybe the identity of the teacher?! (this is also a fact about "Person-Taking-Course"). When you have your entities and attributes, start drawing connections between them -- i.e., the "relationships". In your world, does one student take a single course, or can s/he take many? Check Access HELP on "normalization". Here's a list of other resources from Sandra Daigle: Data Normalization Fundamentals by Luke Chung http://www.fmsinc.com/tpapers/datanorm/index.html Database Normalization Tips by Luke Chung http://www.fmsinc.com/tpapers/genacc...abasenorm.html ACC2002: Database Normalization Basics http://support.microsoft.com/default...b;EN-US;283878 Also check this page for links to several articles and a presentation on Normalization basics: Support WebCast: Database Normalization Basics http://support.microsoft.com/default...lurb060600.asp I generally also recommend the following two books since some people (myself included) still enjoy and benefit from books. a.. Hernandez, Michael. Database Design for Mere Mortals. Reading, MA: Addison-Wesley Developers Press, 1997. b.. Riordan, Rebecca. Designing Relational Database Systems -- Good luck Jeff Boyce Access MVP "Jim" wrote in message ... Hi I am trying to learn how to design a relational database. I have designed one database in access 97 but it was a flat database file since I didn't know how to do relational ones and needed it done quick. I am using access 2002 to design this one but it will be read from a visual basic program and displayed in an MSHFlexGrid. Attached is an excell file (trimmed down and zipped) with the tables that I need to store, I need to know how to decide how they should be formatted in a database. Some of the tables have colums that are not in other columns. Do I make a database table for each of the tables? Do I make one big table that has all the same colums in it and only make new tables for the colums that are not in all of the tables? Is there some other/better way? How do I know what/how to link the tables so that they are efficient. I figure there is probably alot to consider so I am not asking for the absolute best/fastest/efficient way, just a basic start on how to do it. Also I am not looking to just have someone make the file for me so I ask that if you tell me how to format it to please explaine how/why you are saying to format it that way. The particular file for this data is not realy important I am looking to learn how to make a relational db. Any and all help is appreciated. Thanks in advance! Jim |
Thread Tools | |
Display Modes | |
|
|