shawfactor

This plugin logs all wordpress queries in the current page request as a html comment at the end of your output.
It only does so when the get variable lh_log_queries is set. That variable has three settings. 
1. queries: this logs queries only 
2. hooks: this logs hooks only 
3. both: this logs both hooks and filters
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LH Log Queries and hooks

Decisions not options for query and hook logging

pantsonhead

Admin’s Debug Tool allows administrators to analyze page execution without executing/displaying for non-admin users. 
This can be useful when trying to track slow queries or badly performing plugins or widgets. 
The admin-only nature of this plugin can also be useful when trying to track issues that only occur on production servers.

Admin's Debug Tool

Admin-only tool for checking execution times and error output of current theme/plugins

LH Log Queries and hooks vs Admin's Debug Tool