I don't understand why you need both the <explain> xml style tag and the double # to denote an explain entry. I would prefer to see each line prefixed with # explain: to make it similar to the other info lines above and get rid of the <explain>.
By prefixing each line with # explain: it makes grepping explain plans easier than looking for a start and end tag on different lines. On Fri, Oct 18, 2013 at 4:59 PM, Sergei Golubchik <[email protected]> wrote: > Hi, Sergei! > > On Oct 18, Sergei Petrunia wrote: >> Hello, >> >> After recent changes in the [SHOW] EXPLAIN architecture in MariaDB, it became >> really easy to add an option to print EXPLAIN(*) output into the slow query >> log, >> so I went ahead and implemented it. >> >> @@log_slow_verbosity has got a 'explain' flag, and if it is on, the slow >> query >> log entries look like this: >> >> # Time: 131017 21:26:02 >> # User@Host: root[root] @ localhost [] >> # Thread_id: 2 Schema: dbt3sf1 QC_hit: No >> # Query_time: 5.535819 Lock_time: 0.000350 Rows_sent: 1 Rows_examined: >> 65633 >> ## <explain> >> ## id select_type table type possible_keys key key_len ref >> rows Extra >> ## 1 SIMPLE nation ref PRIMARY,n_name n_name 26 const 1 >> Using where; Using index >> ## 1 SIMPLE customer ref PRIMARY,i_c_nationkey >> i_c_nationkey 5 dbt3sf1.nation.n_nationkey 25124 Using index >> ## 1 SIMPLE orders ref i_o_custkey i_o_custkey 5 >> dbt3sf1.customer.c_custkey 7 Using index >> ## </explain> >> SET timestamp=1382030762; >> select count(*) from customer, orders, nation where c_custkey=o_custkey and >> c_nationkey=n_nationkey and n_name='GERMANY'; >> >> It seems, pt-slow-query-log has no problem parsing this. >> >> Open questions: >> >> - Is this syntax OK? > > Yes, assuming you use tabs as column separators, not spaces. > >> - Currently, some statements (like SHOW KEYS) print a dumb explain that >> shows that full table scan is used. There is a suggestion to not print >> EXPLAIN for any SHOW statements. Is this ok? > > Yes. If users will complain we can always change it back later. > > Regards, > Sergei > > _______________________________________________ > Mailing list: https://launchpad.net/~maria-developers > Post to : [email protected] > Unsubscribe : https://launchpad.net/~maria-developers > More help : https://help.launchpad.net/ListHelp -- Eric Bergen [email protected] http://www.ebergen.net _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
