The following two relations R and S have one attribute storing integers. Assume that a join is performed on this attribute. R = { 4, 3, 1, 6, 2, 9, 0, 5, 8, 7 }S = { 3, 4, 5, 8, 0, 2, 1, 6, 7, 9} Show the order of tuples output for the following join algorithms: (for example Sort Join would give (0,0), (1,1),...,(9,9) )

The following two relations R and S have one attribute storing integers. Assume that a join is performed on this attribute. R = { 4, 3, 1, 6, 2, 9, 0, 5, 8, 7 }S = { 3, 4, 5, 8, 0, 2, 1, 6, 7, 9} Show the order of tuples output for the following join algorithms: (for example Sort Join would give (0,0), (1,1),...,(9,9) )

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Let relations r1(A, B, C) and r2(C, D, E) have the following properties: r1 has20,000 tuples, r2 has 45,000 tuples, 25 tuples of r1 fit on one block, and 30tuples of r2 fit on one block. Estimate the number of block transfers and seeksrequired using each of the following join strategies for r1 ⋈ r2: Nested-loop join.
Let relations r1(A, B, C) and r2(C, D, E) have the following properties: r1 has20,000 tuples, r2 has 45,000 tuples, 25 tuples of r1 fit on one block, and 30tuples of r2 fit on one block. Estimate the number of block transfers and seeksrequired using each of the following join strategies for r1 ⋈ r2: Block nested-loop join.
Give pseudocode for computing a join: r ⋈r.A=s.A s using a single MapReduce step, assuming that the map() function is invoked on each tuple of r and s. Assume that the map() function can find the name of the relation using context.relname().
How to code in Python or Java below Algorithm # 10 General Algorithm for Testing Loosless Join DecompositionInput: A universal relation R, a decomposition D={R1,R2,...Rm}of R , and a set F of functional dependencies.1. Create an initial matrix S with one row for each relation Riin D, and one column for each attribute Aj in R.2. Set S(i,j)= bij for all matrix entries.( Note that each bij isa distinct symbol associated with indices (i,j) ).3. For each row i representing relation schema RiFor each column j representing attribute AjIF the relation Ri includes attribute Aj then set S(i,j)= aj.( Note that aj is a distinct symbol associated with index j)4. Repeat the following loop until a complete loop execution results in no changes to SFor each functional dependency X→Y in FFor all rows in S that have the same symbols in the columns corresponding toattributes in X.Make the symbols in each column that correspond to anattribute in Y be the same in all these rows as follows:▪ If any of the…
How to code in Python or Java below Algorithm # 10 General Algorithm for Testing Loosless Join DecompositionInput: A universal relation R, a decomposition D={R1,R2,...Rm}of R , and a set F of functional dependencies.1. Create an initial matrix S with one row for each relation Riin D, and one column for each attribute Aj in R.2. Set S(i,j)= bij for all matrix entries.( Note that each bij isa distinct symbol associated with indices (i,j) ).3. For each row i representing relation schema RiFor each column j representing attribute AjIF the relation Ri includes attribute Aj then set S(i,j)= aj.( Note that aj is a distinct symbol associated with index j)4. Repeat the following loop until a complete loop execution results in no changes to SFor each functional dependency X→Y in FFor all rows in S that have the same symbols in the columns corresponding toattributes in X.Make the symbols in each column that correspond to anattribute in Y be the same in all these rows as follows:▪ If any of the…
TRUE OR FALSE In the Relational Data Model, Referential Integrity Constraint is a special kind/case of Foreign Key Constraint. Multiple Inheritance happens when a class has more than one sub-class. This problem can be observed in Programming Languages as well. Given two relations named A and B, if we q-JOIN A and B, the maximum number of attributes in the result relation could be (the number of attributes of A) times(*) the number of attributes of B). * in an SQL SELECT statement means “all the tuples”. In relational algebra, Cartesian Product (X) can be implemented using the q-JOIN operator. Cartesian Product ISA q-JOIN where q-condition always evaluates to true. SQL is based on Predicate Calculus. A query in SQL always specifies what should be included in the query result.
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Let R(A, B, C) be arelational schema with the following functional dependencies :{A— >B,B—>C,C— >A}The decomposition of Rinto (A, B), (B, C).A. Gives a lossless join, and is dependency preservingB. Gives a lossless join, but is not dependency preservingC. Does not give a lossless join, but is dependency preservingD. Does not give a lossless join and is not dependency preserving