On Fri, Feb 24, 2006 at 05:03:58PM -0500, Lane Van Ingen wrote: > I want to use pgStatTuple to analyze performance problems when visiting user > sites; it is a good tool. I know how to set it up; but I couldn't find an > interpretation of what it generates as a result, so I can be sure of > interpreting its output correctly and fully. Have you seen README.pgstattuple? Here's an excerpt: table_len -- physical table length in bytes tuple_count -- number of live tuples tuple_len -- total tuples length in bytes tuple_percent -- live tuples in % dead_tuple_len -- total dead tuples length in bytes dead_tuple_percent -- dead tuples in % free_space -- free space in bytes free_percent -- free space in % It can be educational to create a table to play with and watch pgstattuple's output change depending on what you do (insert, update, delete, vacuum, etc.). > Can anyone help? May also require definition of 'tuple' when used in a > PostgreSQL sense, also. Tuple, row, and record are generally used synonymously; tuple seems to be the more common term in discussions of theory. If that's too broad a generalization then maybe somebody will provide a more precise explanation. -- Michael Fuhr
