Database Management System

Running head: DATABASE MANAGEMENT SYSTEM
Database Management System
Name of the Student
Name of the University
Author’s Note:

DATABASE MANAGEMENT SYSTEM1
Table of Contents
Task 1: Structure Query Language.................................................................................................2
1.1 Data Manipulation Language:...............................................................................................2
1.2 Data Control Language:.........................................................................................................4
Task 2: Data Manipulation..............................................................................................................6
Task 3: Database Testing.................................................................................................................9
3.1 Database Testing Definition and Importance:.......................................................................9
3.2 Testing Process:.....................................................................................................................9
Bibliography:.................................................................................................................................12

DATABASE MANAGEMENT SYSTEM2
Task 1: Structure Query Language
1.1 Data Manipulation Language:
In order to manipulate, record and access data from a database, the users use the data
manipulation language. Selection, insertion, modification and deletion are the core of data
manipulation language in database. The primary aim of the data manipulation language can be
referred to implementation of easy and effective interaction between the system and user. The
data manipulation language can be utilized in the database SQL. The SQL can be used for
manipulating the relational databases. Two kind of DML exists in database such as non-
procedural and procedural. In case of non-procedural, the database admin mentions what type of
data is required. On the other hand, the user defines the method of accessing the data along with
the data to be accessed in procedural data manipulation language.
For making the database applicable to an organizational objective, the database must
have values within it. In order to populate the database with necessary values, the user uses the
insert command. The insert command allows the user to input a row into the database based on
the structure of the database. Few columns of the database can be empty in a row if columns are
defined as nullable but the primary key will always have a value. Syntax for the insert query is
INSERT [INTO] TableName [(ColumnName, ... n)] VALUES ({DEFAULT I NULL I
expression}[, ... n]). The order of the column name and values are respective to each other. If
orders mismatch then database will either store wrong data in column or show an error. If the any
attribute has a value set as default then entering null values would result into saving the default
value instead of null for that column.

DATABASE MANAGEMENT SYSTEM3
The select column is used for fetching data from the database entities or views. The select
column is capable of retrieving data from more than one column. This is possible because of the
referential integrity constraint that make use of foreign keys. The user can also define a condition
for pulling data out of a database tables.
Update: The update query is used by the users for modifying the existing value in single
or multiple columns in a database table. The general form of update command is as following.
UPDATE table_name
SET column_name1 = value1,
column_name2 = value2,
...
column_nameN = valueN,
[WHERE condition]
Taken as an example, an employee has moved from one location to another. This data
needs to be updated in the database so that organization has complete and current data regarding
each employee. Suppose the id of the employee is 1. The query for updating the address of
employee column is as following.
UPDATE employee set emp_address = '95 Capper Street, BINJOUR QLD 4625' where emp_id
= 1;