Hi guys i was mailing at maria-discuss, but i think it a new feature, and want some view point from developers...
check this problem:

connection 1) big select...
connection 2) show processlist 
connection 1) other query
connection 2) kill connection 1 id (i take +- 1 second between show processlist and this command)
connection 1) killed

the problem? the kill connection 1 (KILL thread_id) killed the wrong query
could we implement something like:

KILL [CONNECTION | QUERY] thread_id [QUERY "some relative unique query id in this database"]

the relative unique query id, could be:
substr(sha1 or md5 of (thread_id + query start time),0,6)  (6 hex numbers is good?)
it's like a git small hash commit id, 
maybe we could make it more unique... but since i will not use it very often, i think a less intensive work is nice here... a global query id could add more one lock for every query...

example:
KILL 1 QUERY "abcdef"

the "abcdef" = substr(MD5( thread id + query start time ),0,6)

we could add client ip or others unique information about this query, but something that don't increase (ok just a little) the load of a show processlist / select * from information_schema

thanks

--
Roberto Spadim