问题求解，大家帮忙～～
consider the following relation schema
R(a,b) ( a is the key)
S(c,d,e) (c is the key)
where R.b is a foreign key to S.c. R.b, S.c and S.d are of the integer type.
Consider the following SQL query:
SELECT R.a, S.e
FROM R, S
WHERE R.b = S.c
AND S.d = 3
There are 200 tuples in R. Each tuple of R is 200 bytes long. There are
40,000 tuples in S. Each tuple of S is 50 bytes long. The values of S.d is
uniformly distributed over [1, 10]. There is an unclustered dense B+-tree
index on S.c.
Assume the effective page size of the system is 4000 bytes (i.e., exclusively
used to store records). Assume an integer occupies 4 bytes. Size of all
pointers (record pointer or block pointer) is 7 bytes. Assume the fill factor
of the B+-tree is 60%. The number of available buffer pages is 10. All costs
are calculated in terms of number of disk I/Os.
Question:
1.Identify the relational algebra tree that a heuristic-based query optimizer
will choose as the best logical query execution plan.
2.Calculate the height of the B+-tree?
3. 有图，贴不了阿～～
4. 。。。。
5. 。。。。
3,4,5三道题，都有图， 大家能告诉我应该怎么把问题放上来么？， 直接说不明白问题！！
谢谢大家帮忙！！！！！！
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