In this book, we’ve looked at different ways to tackle a variety of categories of queries. However, even if a query retrieves some valid-looking rows, all may not be well. In the previous chapter, we looked at the importance of checking the output to confirm that (at least some of) the expected rows are retrieved, as well as checking to make sure that (at least some) incorrect (or irrelevant) rows are not being returned.
The problems that can befall queries are not just a matter of having the wrong syntax in SQL statements, although that can certainly happen. Problems with ...
