Queries Ask Questions
You discovered in the last chapter that the table is the heart of the database. A good database plan can help you organize your table data. But organization is not the only function of a database. You might need to compare last year’s table with this year’s table. Or you might want to update one field’s data throughout the entire table. Or you might need to compute the sales tax on all the invoices in the table. And the list goes on. In other words, you need a vehicle that can manipulate and examine data in a variety of different ways.
What is a query? It is simply a program that asks a question pertaining to table data. You can consider a query a description of the records you want to retrieve from your table data. That ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access