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copied!<p>I would contend that having to use many joins (e.g. deal with normalized data) is not a code smell, but rather an indication you might not be working in the right place. In my experience, those that are concerned about the number of joins in queries are developing too much in the database and not enough in the applications and reports that expose the data. The data structures must be flexible enough to support a myriad of uses and this is why normalization, to one degree or another, is important.</p> <p>In building today's enterprise applications, developers can leverage yesterday's accomplishments to work at abstract levels high above technologies like SQL, and even XML, in order to deliver more value with less work. There are tools, i.e. Report Writers, Code Generators, ORMs, entity frameworks, etc., that abstract away the low level work of constructing SQL manually, and will perform the joins for you. Most are aware of the SQL dialect being used (for example, Oracle 9 vs MySQL 3) and can generate the SQL syntax that is most efficient for that dialect; meaning they can probably create the joins better than you can. </p> <p>However, these tools work very poorly, or not at all, in a relational environment without sufficient normalization. For me, this is where a "development" smell manifests itself; if an established data access tool can't understand the relations under which I've structured my data, I probably need to look for a more normalized way to create those relationships and therein reap benefits far exceeding just the use of the tool. Typically, somewhere between 2nd and 3rd <a href="http://en.wikipedia.org/wiki/Database_normalization#Normal_forms" rel="nofollow noreferrer">normal form</a> is the sweet-spot; although invariably there tend to be small areas of relational data where a higher degree of normalization makes sense and adds value.</p> <p>Cheers, Travis</p>

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