WebAppGeneXpress_How_To_Presentation
- 1. WebAppGeneXpress Includes Relational Database Design Tips http://www.supertime2000.com
- 2. Divide your information into one or more tables, each made up of fields (which are like the columns in a spreadsheet). orders •ID •ddate •custId •shiptype •terms items •ID •orderId •pricesId •quantity cust •ID •mrms •company • firstname • lastname •region •stateId •zip prices •ID • idescrptn •price states •ID • state • tax
- 3. Using relational joins in WAGX (NOT Access), where a field in one table matches (relates to) a field in another.
- 4. Known as Master Table in WAGX
- 6. Make a list of the possible fields (pieces of information), including only text, numeric and date. Numerics can be Integer, Long Integer, Double or Decimal.
- 7. Don’t store the same information in more than one place. If you can calculate one field from another, store only one. (For example, store birth date or age, but not both.)
- 8. Group your fields according to what they describe, so each group becomes a table. For example, an order entry database for a store might have one table for customers, one for products, and one for orders.
- 9. Plan to include table for every code or abbreviation you plan to use in the database. You’ll use these tables to create dropdown lists of values you can choose from when entering records.
- 10. The primary key is the field that uniquely identifies each record in the table. You can tell Access to assign a unique ID number to each record by using an AutoNumber, Long Integer ID field. WAGX recognizes only ID (Uppercase) as Primary Key.
- 11. See which tables contain fields that match fields in other tables. In an order entry database, the Orders table must contain a field to identify the customer who has placed the order - a field to match the primary ID key field in the Customers table. Relationships can be one-to-many, where one record in one table can match more than one (or none) records in another table.
- 12. For example, ordered Item Quantity may need to be multiplied with Rate to derive Value.
- 13. It is possible to Sum/Min/Max/Count/Average Table/Calculated columns. For example, the sum of all Item Values can give Order Value.
- 14. Some table fields may be redundant for display in an application view.