I am working in a tool for people to run to autotune a query, and would like to use the info. It could also be of use to the optimizer in shard query to make adaptive choices about query execution.
Sent from my iPhone > On Feb 14, 2014, at 9:15 PM, Colin Charles <[email protected]> wrote: > > >> On 15 Feb 2014, at 13:01, Justin Swanhart <[email protected]> wrote: >> >> Workbench uses EXPLAIN FORMAT=JSON which is different from optimizer trace. >> Optimizer trace allows us to very accurately determine what indexes were >> used, why ICP was picked, etc. It allows us to see when things like the >> exists strategy is used for a subquery instead of materializing it. Lots of >> very great stuff from it that is not available from EXPLAIN FORMAT=JSON. > > i was under the impression that besides just EXPLAIN FORMAT=JSON, workbench > could also display the optimizer trace info (from a presentation i saw on > this @ mysql connect 2013). that said, i've never tried said feature with > workbench (i don't generally use workbench) > >> The optimizer trace information is available in a special information schema >> table. > > yes, this i know. it is something we clearly are missing (besides, EXPLAIN > FORMAT=JSON) > > do you know any tools that make use of it though? depend on it? i mean usage > within mysql 5.6 is something along the lines of: > set optimizer_trace="enabled=on"; > select * from foo; > select * from information_schema.optimizer_trace; > > i'm just curious if we're accidentally breaking anything/functionality for > something else? > (you mentioned this too: "Writing tools to support competing implementations > of the same feature is not fun.") > > cheers, > -colin > >> >> On Fri, Feb 14, 2014 at 8:23 PM, Colin Charles <[email protected]> wrote: >> >> On 15 Feb 2014, at 11:35, Roberto Spadim <[email protected]> wrote: >> >>> here: >>> https://lists.launchpad.net/maria-developers/msg05719.html >> >> isn't this just the standard DBUG_ENTER(), DBUG_PRINT() of the SE API? >> >> extracts from https://mariadb.com/kb/en/plans-for-10x/ : >> • QA request: better EXPLAIN (HIGH priority; MP; Spetrunia) >> • required in order to debug performance issues in queries >> without knowing the query or the data; >> • the customer will only provide EXPLAIN and SHOW output, we >> need to debug based on that; (need examples) >> • Perhaps optimizer trace is what we need >> >> • U/C at Oracle: OPTIMIZER tracing spetrunia: report actual >> estimates, and all decisions of the optimizer, including why an index was >> *not* picked, etc. >> • want to change for 5.7 >> >> >>> 2014-02-15 1:21 GMT-02:00 Justin Swanhart <[email protected]>: >>> Can you point to the docs on the mariadb implementation? Writing tools to >>> support competing implementations of the same feature is not fun. >> >> i don't think they are the same feature. optimizer tracing, and its >> accompanying json output is something that mariadb 10.0 will not have, but >> something we probably need in future versions (10.1) to remain "backwards >> compatible". >> >> i see mysql workbench as a front-end tool supporting optimizer trace -- do >> you know of more justin? >> >> cheers, >> -colin >> >> >>> >>> >>> Sent from my iPhone >>> >>>> On Feb 14, 2014, at 2:12 PM, Roberto Spadim <[email protected]> wrote: >>>> >>>> that's the "same" feature of dbug in mariadb >>>> >>>> >>>> 2014-02-14 19:01 GMT-02:00 Tim Callaghan <[email protected]>: >>>> Is this feature or something similar already in MariaDB 10? If not, is it >>>> on the roadmap? >>>> >>>> http://dev.mysql.com/doc/internals/en/optimizer-tracing.html >>>> >>>> -Tim Callaghan >>>> >>>> _______________________________________________ >>>> Mailing list: https://launchpad.net/~maria-discuss >>>> Post to : [email protected] >>>> Unsubscribe : https://launchpad.net/~maria-discuss >>>> More help : https://help.launchpad.net/ListHelp >>>> >>>> >>>> >>>> >>>> -- >>>> Roberto Spadim >>>> SPAEmpresarial >>>> Eng. Automação e Controle >>>> _______________________________________________ >>>> Mailing list: https://launchpad.net/~maria-discuss >>>> Post to : [email protected] >>>> Unsubscribe : https://launchpad.net/~maria-discuss >>>> More help : https://help.launchpad.net/ListHelp >>> >>> >>> >>> -- >>> Roberto Spadim >>> SPAEmpresarial >>> Eng. Automação e Controle >>> _______________________________________________ >>> Mailing list: https://launchpad.net/~maria-discuss >>> Post to : [email protected] >>> Unsubscribe : https://launchpad.net/~maria-discuss >>> More help : https://help.launchpad.net/ListHelp >> >> -- >> Colin Charles, Chief Evangelist >> MariaDB | t: +6-012-204-3201 | Skype: colincharles > > -- > Colin Charles, Chief Evangelist > MariaDB | t: +6-012-204-3201 | Skype: colincharles > _______________________________________________ Mailing list: https://launchpad.net/~maria-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-discuss More help : https://help.launchpad.net/ListHelp
