MySQL Enterprise Monitor offers a tool called "Query Analyzer" (QuAn). QuAn sits between any client app and the MySQL server and logs every query and its runtime statistics. A very cool tool for analyzing your SQL. More information is available here.If you identify a query, that needs some improvement, sometimes it is hard to identify the source of that query as well. With hundreds of different PHP scripts for example it is not easy to know, which one issued the query, that you want to modify.A good way to achieve this is adding C-style SQL comments. Let's look at an example: SELECT * FROM mytable …

The MySQL Enterprise Monitor continuously monitors MySQL servers and alerts to potential problems before they impact the system. It helps eliminating security vulnerabilities, improves replication, optimizes performance, and more. Its newest feature, Quan (Query Analyzer), helps identify queries that could be tuned to improve performance. Quan enables database administrators to do the work that would otherwise require hours in just minutes, or even seconds, and it provides ongoing statistical information about the performance of your queries.

MySQL Enterprise Monitor is a commercial offering by Sun Microsystems, and so was the documentation. To help anyone (even if they're not customers) get a better and complete understanding of what exactly MySQL Enterprise Monitor is about and what it can do, we've decided to make its full documentation publicly available. This has been done now, and the docs are part of the MySQL Manual now; see: …

I see that Sun prominently quoted one of our Engineers in their recent press release for Query Analyzer (Quan).  He’s a bit embarrassed by the attention, but his quote is spot on… Quan is a really solid and useful product.

Of course, there is nothing there that you can’t get by combining various tools like mysqlsla, innotop, mysqlreport and spending some time in analysis.  What Quan adds is making the information readily available, and letting someone without expert level …