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Have you read Chapter 2 of the Base Guide? (Planning/Designing your database) There are 56 pages in which I used this approach for all the parts of a database. There are many questions in it designed to help a person.


On 02/14/2013 07:39 PM, Girvin R. Herr wrote:
This is good! It is a good start on an introduction to databases for newbies.
It should be put in the Base manual?
Girvin Herr

Dan Lewis wrote:
      Some basics about creating a database:
1) You begin with data that you want to use for some purpose or purposes. 2) Then you design the database to organize this data so that it will be useful.

For example: an address database:
In the beginning, the database consists of information such as names, addresses, email address, phone numbers, etc. The first thing you would want to do is to organize this data so that a name is linked to its address, its email address, its phone numbers, etc. Now you have rows of data, each one of them containing information about a single person (a relationship exists between the data for each row). Each of these pieces of information is a field. If you look at these rows, you will see that they also contain some things in common. Several rows can contain data about your friends, others are about your relatives, and others are about companies you do business with. You probably know of other possibilities. So, these rows can be organized into groups based upon what they have in common. (This too is a relationship.) The next thing you should do is to further organize these rows in each one of these groups to make them more useful. You could form a table using these as the column headings: name, address, email address, and phone number. ( Now you have a table for each group of rows. So, if you want data about a particular contact, you can go to the table that contains it. If you want to look at the data for a relative, you go to the table containing all of your relatives. This is basically how a flat database is created. Relational databases begin in the same way. At this point, each of these tables are checked to see whether they are "normal" or not. For example, a contact is likely to have multiple phone numbers or other possible multiple entries. Each of these have something in common (another relationship). We can remove the field containing multiple entries forming a new table. To keep the relationship between this new table with the original table, we create a primary-foreign key pair (the primary key is for the new table, and the foreign key is added to the original table in place of the fields we removed.) This is what is done to make a table "first normal form". There are several levels of a table being normal: "first normal form" to "fourth normal form" and beyond. "Fourth normal form" is considered to be the standard against which a table should be judged. The point being that we do not create tables with their fields and then define the relationship between them. We begin the the fields that we know we will need, combine the fields based upon relationships between data, and combine the fields into tables based upon relationships between the fields. The the tables are normalized up to "fourth normal form" creating new tables and modifying the old ones. Primary-foreign key pairs are used to define the relationship of the new tables and the modified old table from which the new table came.
     Hopefully this will help some.


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