Database Query Log is a module targetted at Drupal developers and inquisitive admins. Similarly to Devel module, it can save database queries executed by Drupal to its own table, allowing to browse and filter through them afterwards. It also can print all executed queries at the bottom of each page.
What differentiates it from Devel is that it is much more specialized. While Devel saves only overview of each query (without values), this module saves complete queries, exactly as they were executed. It also allows to filter queries to save/discard based on calling function and/or path.
Additionally it provides Recent Database Queries report (similar to Recent Log Entries), allowing to easily browse through all saved queries and filter them based on various criteria.
Created mainly for development purposes, not recommended to be used on production (especially high-traffic) sites.
Available from github.