# Recent questions tagged indexing

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The minimum number of nodes (both leaf and non-leaf) of $B^{+}$ tree index required for storing $5500$ keys and order of $B^{+}$ tree is $8$________________(order is max pointers a node can have) See here first level should be divide by $7$ $2nd$ levelshould divide by ... each $7$ pointer of 1st level has $8$ pointer in 2nd level. Am I missing something?? But in ans they divided by only $8$ :(
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Consider the following statement below: $A)$ A clustered index may be either sparse or dense. $B)$ Every $B^{+}$ tree index is dense. Which of the above statement is true? Is clustering Index can be dense. Dense means non-ordering field, but clustering field should be ordering field right??
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Construct a $B^+$-tree for the following set of key values: $(2, 3, 5, 7, 11, 17, 19, 23, 29, 31)$ Assume that the tree is initially empty and values are added in ascending order. Construct B+-trees for the cases where the number of pointers that will fit in one node is as follows: a. Four b. Six c. Eight
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Is it possible in general to have two primary indices on the same relation for different search keys ? Explain your answer.
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What is the difference between a primary index and a secondary index ?
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Since indices speed query processing, why might they not be kept on several search keys ? List as many reasons as possible.
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When is it preferable to use a dense index rather than a sparse index ? Explain your answer.
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Q Consider a relation R(a, b, c) ordered on a non-key attribute b, and an index is maintained on attribute c. To evaluate the following expression, which is a better order of operation? σ(b= abc'∧c=12)(R) A. First filter tuples using index on c and then ... First search tuples for the given value of b and then use index on c C. The order of operation does not matter D. Insufficient data to answer
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among primary index, secondary index, clustered index which index are dense or sparse or both?
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I am confused about indexing being densed or sparse, Read a lot of answer but can't figure out Primary Index is always sparse : since indexing is done of key attribute and records(files) are ordered so we create index only for anchor of the block(group of records). ... record and is only for some records. Please correct me If I am wrong at some point and If I am right then please comment.
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Can anyone suggest me any useful source from where I can read b+ tree insertion and deletion?
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suppose that in a file organization record size(R)=150 bytes , block size (B)=512 bytes. there are totally 30000 records. the data field on which indexing is done is 9 bytes and block pointer size is 7 bytes how many block access will be needed to access a data item in case of single level primary indexing?
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Can anyone explain this in detail???
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Consider a $B^+$ tree , in which order of internal nodes is 4 and order of leaf nodes is 3. The order of internal nodes is the maximum number of tree pointers in each internal node and the order of leaf node is the maximum number of data items that can be stored in each ... below way and I got 3 splits, assuming B+ tree with left biasing. But the answer is given to be 8. Have I made any mistake?
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what is the minimum and maximum number of keys for non-leaf nodes and leaf nodes for B+ Tree of order p?
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can anyone share some good resources fot B+ tree deletion?
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I have two doubts here (1)Doubt1-The number of blocks needed to store file must be 3000 and not 2930. Record organisation is unspanned and so 1 block can contain only 10 records. Here in solution, they are trying to fit bytes into blocks and not records ... they didn't tell, for purpose of optimisation we can consider multi-level indexing with primary index. What should be the correct answer here?
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How to prove that if same size blocks are allocated to B trees and B+ trees then:- No. of index nodes in B tree >= No. Of index nodes in B+ tree
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Block size 1000B records are of size 100B of which 12B are the key field and pointer of size 8B. a file consist of 10000 records 1.the number of blocks required for a sparse index on this file? 2.the number of blocks required for for a dense index on this file
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Here the indexing is done on ordered field so which to use Dense or Sparse because both can be done here ?
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Please Solve this question. I didn't understood the question properly so please Make Me as well :) What is meant by Leaf Page ?
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1. Why in question They treat both clustered and primary indices Different, because both are the same thing(written in Korth). Only the thing is Primary indices means search key is Primary Key and Clustered means it can be any search Key and both defines the same ... a clustered index and i took another attribute not in the order say Salary and created a different Secondary index on the Records ?
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Database file consist 50000 records with record size 100 bytes, block size 512 bytes. If sparse B+ tree index build over given database file with search key size 20 bytes both block pointer and record pointer sizes 12 bytes each. How many maximum index blocks required if node order P is defined as between ⎡P/2⎤ to P pointers per node?
A database relation has $5000$ records block can hold either $10$ records or $15$ keys and pointer pairs. If sparse index is used at $1^{st}$ level and multilevel indexing is used in system, then the number of disk block required to store relation and index is _______. 1. Please explain the approach used. 2. what had been the answer if instead of sparse it would have been dense indexing ?
Which of the following statements true for $B$ tree and $B^+$ tree index? A. $B$ tree index faster for range queries compare to $B^+$ tree index. B. If disk block allocated for $B^+$ tree index and same size disk block allocated for $B$ tree index then number of index ... cost of $B^+$ tree index less than equal to I/O cost of $B$ tree index for random access of same key from set of distinct keys.