Hi: Thank you all for kindly replying.
I think that I need this: pg_stat_user_tables.n_tup_hot_upd And Adrian's information is a pretty good material for me to understand the internal. Best regards 2013/8/22 Adrian Klaver <adrian.kla...@gmail.com> > On 08/21/2013 07:20 PM, 高健 wrote: > >> Hi: >> >> I have heard that Heap-Only Tuples is introduce from 8.3. >> And I am searching information for it. >> >> How can I get a detailed information of HOT? >> > > http://git.postgresql.org/**gitweb/?p=postgresql.git;a=** > blob;f=src/backend/access/**heap/README.HOT;hb=HEAD<http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/access/heap/README.HOT;hb=HEAD> > > > For example: >> according to a table, How many tuples are heap only tuples , and how >> many are not? >> >> And also , Is there any options which can influence HOT occurrance? >> >> Best Regards >> > > > -- > Adrian Klaver > adrian.kla...@gmail.com >
