in the past, i’ve mostly used SQLiX from owasp, as well as a few manual methods (mostly using Burp). if you want the latest on Overlooked SQL Injection techniques, look no further than Paul Battista, who i recently saw give this talk at toorcon 9 in san diego.

dave aitel and jms also put together a sort of proxy fuzzer/monitor (basically an RDBMS spy) called SQL Hooker, which is certainly worth a look at. i think bestorm does something similar in their products. immunitysec is also working on a similar tool that would help with file monitoring to increase the intelligence behind manual or automated web application black-box security testing