Usage Considerations: Simple and Complex Queries
Users query their databases not because they need an answer as an end result; rather, they want guidance for performing a business action that will have optimal decisive effects. The actions taken cause your bottom line to change, not the answers that informed those actions.
A query can be simple or it can be complex. The answers provided by simple queries tend to be more expected than not, while the answers provided by complex queries tend to produce far less certain answers that are that much richer for resolving the questions they pose.
Consider the following case example from the financial industry. A bank offers its customers a financial instrument that a competitor has decided to offer “without charge.” This challenge must be responded to quickly or the bank will lose many of its customers who are currently paying what they see as an unnecessary fee for the financial instrument under discussion.
Suppose the bank responds to this situation by asking a simple question such as “which current customers use this product”? The most likely response to this information, which is merely a list of current customers, would be to eliminate the fee for the product. While this action is likely to forestall the erosion of the customer base, it also has the negative effect of reducing profits for the bank.
Suppose, instead, that the bank asks a more sophisticated question such as “which current customers using this product would remain profitable clients even if the fee were eliminated”? The bank now knows not only which consumers of its financial instrument are profitable for reasons other than their consumption of that product, but also knows which consumers do not otherwise contribute to the bottom line. The latter customer set can be released to the competition, which, by the way, almost certainly does not know that the new customers it is luring away from our bank are not profitable.
The impact of this more complex query is profit maximization, and its example illustrates very clearly the value of complex over simple queries.