Performance evaluation...o(1),O(n),O(n?2),O(logn)?

题目

Performance evaluation...o(1),O(n),O(n?2),O(logn)?
hi therelet say that i have 400 entry in mara in devconsidering that i am using select single on mara.what is the order of performance associated to this select single?it is O(n)?i.e.400 entry ±= 400 seconds => 33000 entry ±= 33000 seconds?it is O(n?2)?i.e.400 entry ±= 160k seconds => 33000 entry ±= 1089M seconds?any places i can find this kind of info for differents calls?i would like to know approximatly the time it takes before it go in prod or even in QA...thanks

答案

It really depends on how good your DBA is and how tuned the database is? The same query can run in very different amounts of time based on the optimization of the database at the time of the run. 查...