Computer Science - Distributed Databases

Question 1 1 . Among the five , we should create an unclustered hasheesh forefinger on (ename , age , sal ) fields of Emp (b ) since we could only do an force scan for us to speed up the school principal . If our system does non include index only architectural plans indeed we shouldn t create an index for this doubtfulness (e . However since this query requires us to access all Emp . records , an index would really uphold us anything at all . Therefore , we should access the records use a scan2 . For this case , we should create clustered dense B shoetree index (c ) on (floor , budget ) fields of Dept , because the records bequeath be organized under these fields . Thus , if we pass and lean this query , the first record with floor 10 should be retrieved the while the other records with floor 10 should be evidence in the of the budget .

Note that this plan is not an index-only plan (must look up didsQuestion 2We should place the in the middle of the tracks because collectioned speed is not an issue due to the small surface of it of the . Apart from that , the seek time is minimized when s be place in the centerFor this case , we should place the and index on the inner tracks The DBMS will alternately access the pages of the index and the thus , the two should reside in close propinquity in to reduce seek times . By doing so , we will also...If you want to get a full essay, instal it on our website: OrderEssay.net

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