计算机代写|ST207 Database

MY-ASSIGNMENTEXPERT™可以为您提供lse.ac.uk ST207 Database数据库课程的代写代考辅导服务!

这是伦敦政经学校数据库课程的代写成功案例。

计算机代写|ST207 Database

ST207课程简介

This course is compulsory on the BSc in Data Science. This course is available on the BSc in Actuarial Science, BSc in Mathematics, Statistics and Business and BSc in Politics and Data Science. This course is available with permission as an outside option to students on other programmes where regulations permit and to General Course students.

This course has a limited number of places (it is capped). Students who have this course as a compulsory course are guaranteed a place. Places for all other students are allocated on a first come first served basis.

Prerequisites 

The goal of this course is to cover basic concepts of database management systems, including relational and other types of database management systems.

The topics covered will include basic concepts of the relational model, creating and modifying relations using Structured Query Language (SQL), basic SQL queries using SELECT operator, nested queries, aggregate operators such as GROUP BY, integrity constraints and relations, views, application development using JDBC, Internet protocols such as HTTP and XML, storage and indexing, tree-structured indexing using B+ trees, hash-based indexing, query evaluation and algorithms for relational operations, external sorting, transaction management and concurrency, database schema and normal forms, and overview of NoSQL databases such as key-value stores, document, and graph databases.

ST207 Database HELP(EXAM HELP, ONLINE TUTOR)

问题 1.

With the use of a diagram, explain the different levels of architecture of a database system.

Explain the acronyms DSL, DML, DCL, and DDL. How are they related?

Identify the main personnel in a DBS environment. What are the primary functions of each role?

What are the main functions of the DBMS?

With the aid of an appropriate diagram, explain how the DBMS ensures that requests from end users are satisfactorily addressed.

Discuss the functional components of a DBMS. Use an appropriate diagram to illustrate.

Explain the concept of front-end and back-end systems, and show how they add flexibility to the implementation of distributed database systems.

问题 2.

For traditional relationships, to determine the type of relationship between two relations (entities) R1 and R2, ask and determine the answer to the following questions:

How many records of $\mathrm{R} 1$ can reference a single record of R2?

How many records of R 2 can reference a single record of R1?
To test for a component relationship between any two relations R1 and R2, ask and determine the answer to the following questions:

Is (a record of) $\mathrm{R} 1$ composed of (a record of) $\mathrm{R} 2$ ?

Is (a record of) $\mathrm{R} 2$ composed of (a record of) R1?
For a subtype relationship, the test is a bit more detailed; for relations R1 and R2, ask and determine the answer to the following questions:
Is (a record of) R1 also (a record of) an R2?
Is (a record of) $\mathrm{R} 2$ also (a record of) an R1?
Possible answers to the questions are always, sometimes, or never. The possibilities are shown in Table 3.3. Notice that of the nine possibilities, only two outcomes are useful: R1 is a subtype of $R 2$, or $R 2$ is a subtype of $R 1$.

问题 3.

Notice that we have glided into two new terms, projection and join. These will be formally treated later in the course. Suffice it for now to say that a projection on a relation is an extraction (into a new relation) of some attributes of the original relation; a join requires at least two relations and may be construed as the opposite of a projection: If you can project R into P1 and P2, then you may be able to join $\mathrm{P} 1$ and $\mathrm{P} 2$ to yield $\mathrm{R}$.

So, has it occurred to you that identifying FDs and managing NLDs are two imperatives for the normalization process? Indeed, they are! Given this definition of an NLD, we need to address the following questions:

  1. How do we find non-loss decompositions?
  2. When should we replace a relation by a non-loss decomposition?
  3. What are the advantages?

问题 4.

State the two fundamental integrity rules and explain their significance.

What is a foreign key? Illustrate using an appropriate example. How should foreign keys be treated?

Clarify the following: functional dependence; non-loss decomposition; Heath’s theorem. Provide examples that will illustrate the significance of these terms.

State the normal forms covered in this chapter. For each normal form, state it, explain in your own words what it means, and provide an example of a relation that conforms to it and one that does not.
5 What are the main advantages and challenges related to database normalization?

Review the case presented in Section 4.9.2 and propose a refined RAL for the CTT-Schedule problem.

Review the case presented in Section 4.9.3 and propose a refined RAL for the Zoo problem.

计算机代写|ST207 Database

MY-ASSIGNMENTEXPERT™可以为您提供LSE.AC.UK ST207 DATABASE数据库课程的代写代考和辅导服务!

发表评论

您的电子邮箱地址不会被公开。 必填项已用 * 标注