The first step in working with VisiconX is planning what information you want to obtain. For example, sales may want a list of all customers whose orders were shipped after the required date so that they can offer special incentive packages for future orders.
This means finding out what database to query and obtaining privileges to access data in the database. It also means finding out how information is organized in the database so that you can determine what tables to access.
Once you have determined where and how information is organized, you should determine how to construct a query that returns the precise information you want. That means finding out:
- What table or tables to query. If you query more than one table, what column should they be joined on and should the join by an inner join or an outer join?
- What columns to include in the query and the order in which they should appear. Do you want to see duplicate rows or not?
- What comparison expressions to use in the row filter and whether to combine the expressions using an And operator or an Or operator.
- How to sort the information returned.
You may need to create multiple queries, especially in a situation where the data residing in one database determines the data retrieved from another database. In each case, use the considerations listed in the preceding bullets to return the information you need.
