Structured Query Language and Server Services PDF

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Running head: STRUCTURED QUERY LANGUAGE AND SERVER SERVICES
Structured Query Language and Server Services
Student’s Name
School Affiliation

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STRUCTURED QUERY LANGUAGE AND SERVER SERVICES
Table of Contents
Question 01......................................................................................................................................3
Question 03......................................................................................................................................6
References......................................................................................................................................14

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STRUCTURED QUERY LANGUAGE AND SERVER SERVICES
Question 01
a) Evaluate normalization. Explain why normalization is required in the good database
system.
Database normalization – refers to the method of arranging columns as well as tables of a
relational database to minimize redundancy of data and advance the data integrity as well as the
efficiency of information stored. Normalization can also refer to the approach in which poorly
made tables are decomposed through breaking up table attributes into smaller tables which have
desired features (Coronel, and Morris, 2016). Normalization organizes attributes in tables in
respect of dependencies between attributes, guaranteeing that the dependencies are correctly
emphasized by the integrity of database constraints. Normalization might be obtained by
deploying formal policies such as synthesis as well as decomposition. There are several kinds of
normalization which include the following:
1NF – First Normal Form – here no two rows of details should consist of a repeating group of
data, every table should be arranged into rows as well as every row must possess a primary key
which differentiates it as unique.
2NF – Second Normal Form – here it is compulsory to have any partial dependency of every
column on key which is primary implying that for a table which possesses concatenated key that
is primary, every column of the table which is not portion of the primary key should rely upon
the whole concatenated for availability, failing that the table fails Second normal form.
3NF – Third Normal Form – this is database rule that permits you to correctly organize our
tables by creating upon the normalization of database rules offered by 1NF as well as 2NF.
BCNF – Boyce Codd Normal Form – this form is concerned with a kind of anomalies which are
not addressed by 3NF, therefore, a 3NF table that does not possess multiple overlapping
candidate keys is termed to be BCNF.
4NF – Form Normal Form – this is compulsory to meet the whole needs of 3NF. Attributes from
one or many rows of the table might not lead in more than one rows the similar table resulting in
multi-valued dependencies.

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STRUCTURED QUERY LANGUAGE AND SERVER SERVICES
The normalization techniques aids in eliminating data redundancies which cannot be controlled,
hence eliminating the information anomalies as well as the integrity of data challenges which are
generated by such redundancies. Normalization can create controlled redundancy which lets us
correctly connect database tables, however, redundancy in the data is not needed, again
manageable redundancies are included in order to meet the requirements of the users as well as
the efficiency of processing. This is attained by taking the ordered method using normalization in
order every table in the database depicts only a single object, whole attributes are identified by
one key of the table which is primary, and that no information is stored more than one table
except it is relevant (Zheng et al., 20015). Normalization guarantees that the attributed linked
together in such a way in which redundancies are eliminated otherwise in it is controlled. The
presence of data redundancies brings challenges in the database especially while updating and
these problems can result in inconsistencies of data, an update of data anomalies as well as issues
of data integrity.
b) Using the student records shown below, draw a dependency diagram and convert this
table into 3NF (3rd normal form).
DEPT_CODESTU_LNAMESTU_NUM
ADVISOR_LNAME STU_CLASSADVISOR_BLDGADVISOR_OFFICE