Addendum CS403

Lecture No. / 1
Suggestion type / New Database Management Tools
Artifact / Video lecture
Placement on Time Line / Page no. / 50:00
MySQL Tools
Oracle Tools
PostgreSQL Tools
DB2 Tools
MaxDB Tools
Lecture No. / 2
Suggestion type / New Example Added
Artifact / Video lecture
Placement on Time Line / Page no. / 1:50 - 2:40
Data is a collection of facts, figures and statistics related to an object. Data can be processed to create useful information. Data is a valuable asset for an organization.
Example
Students fill anadmission formwhen they getadmission incollege.The formconsists of raw facts about the students. These raw facts are student's name, father name, address etc. The purpose of collecting this data is to maintain the records of the students during their study period in the college.
Lecture No. / 2
Suggestion type / Adding Database Application
Artifact / Video lecture
Placement on Time Line / Page no. / 5:25 - 6:25
Database systems are widely used in different areas because of their numerous advantages. Some of the most common database applications are listed here.
  • Airlines and railways:Airlines and railways use online databases for reservation, and for displaying the schedule information.
  • Banking:Banks use databases for customer inquiry, accounts, loans, and other transactions.
  • Education:Schools and colleges use databases for course registration, result, and other information.
  • Telecommunications:Telecommunication departments use databases to store information about the communication network, telephone numbers, record of calls, for generating monthly bills, etc.
  • Credit card transactions:Databases are used for keeping track of purchases on credit cards in order to generate monthly statements.
  • E-commerce:Integration of heterogeneous information sources (for example, catalogs) for business activity such as online shopping, booking of holiday package, consulting a doctor, etc.
  • Health care information systems and electronic patient record:Databases are used for maintaining the patient health care details.
  • Digital libraries and digital publishing:Databases are used for management and delivery of large bodies of textual and multimedia data.
  • Finance:Databases are used for storing information such as sales, purchases of stocks and bonds or data useful for online trading.
  • Sales:Databases are used to store product, customer and transaction details.
  • Human resources:Organizations use databases for storing information about their employees, salaries, benefits, taxes, and for generating salary checks.

Lecture No. / 2
Suggestion type / New concept
Artifact / Video lecture
Placement on Time Line / Page no. / 32:20
System Analyst: System Analyst determines the requirement of end users, especially naïve and parametric end users and develops specifications for transactions that meet these requirements. System analyst plays a major role in database design, its properties; the structure prepares the system requirements statement, which involves the feasibility aspect, economic aspect, technical aspect etc. of the system.
Lecture No. / 4
Suggestion type / Adding more detail
Artifact / Video lecture
Placement on Time Line / Page no. / 33:13:00
Data Dictionary Management:The DBMS stores Metadata (i.e. definitions of the data elements) in a data dictionary. All the programs that access the data in the database work through the DBMS. The DBMS uses the data dictionary to look up the required data component structures and relationships. Additionally, any changes made in a database structure are automatically recorded in the data dictionary. Thus, the DBMS provides data abstraction, and it removes structural and data dependency from the system.
Data storage management:The DBMS creates and manages the complex structures required for data storage. A modern DBMS provides storage not only for the data, but also for related data-entry forms or reports, data validation rules, code, structures to handle video and picture formats, and so on. Data storage management is also important for database performance tuning. The DBMS actually stores the database in multiple physical data files.
Lecture No. / 4
Suggestion type / Example of catalog
Artifact / Video lecture
Placement on Time Line / Page no. / 34:48 - 36: 51
CAT is a table (view) from the data dictionary.
For example we have tables of STUDENT, TEACHER, REGISTRAR etc, from this scenario the catalog will be
Catalog
TABLE_NAME / TALBLE_TYPE
STUDENT / TABLE
TACHER / TABLE
Lecture No. / 4
Suggestion type / Adding more detail for selection of a particular DBMS
Artifact / Video lecture
Placement on Time Line / Page no. / 41:12:00
Based on Number of Sites (Locations):
Depending on the number of sites over which the database is distributed, it is divided into two types, namely,centralizedanddistributed database systems.Centralized database systemsrun on a single computer system. Both the database and DBMS software reside at a single computer site. The user interacts with the centralized system through a dummy terminal connected to it for information retrieval. Indistributed database systems, the database and DBMS are distributed over several computers located at different sites. The computers communicate with each other through various communication media such as high-speed networks or telephone lines. Distributed databases can be classified ashomogeneousandheterogeneous. Inhomogeneousdistributed database system, all sites have identical database management system software, whereas inheterogeneousdistributed database system, different sites use different database management system software.
Lecture No. / 4
Suggestion type / Adding detail of 2-tier and 3-tier architecture
Artifact / Video lecture
Placement on Time Line / Page no. / Interval: 50:30
Two-tier architecture:
Two-tier architecture is a software architecture in which a presentation layer or interface runs on a client, and a data layer or data structure gets stored on a server. Separating these two components into different locations represents two-tier architecture, as opposed to single-tier architecture.
Three-tier architecture:
3-tier architecture is a client server architecture where the user interfaces, computer data storage and data access are created and maintained as independent modules. It is mean to allow any of the three tiers to be replaced or developed independently. For example, a change in the operating system of a presentation tier will only affect the user interface code.
Lecture No. / 5
Suggestion type / Names of Tools for database design
Artifact / Video lecture
Placement on Time Line / Page no. / 20:00:00
Some tools for database design are given below:
ERStudio
Microsoft Visio
Rational Rose
PowerDesigner
TOAD Data Modeler
Lecture No. / 5
Suggestion type / Some important web links for the current Lecture.
Artifact / Video lecture
Placement on Time Line / Page no. / At the end of the lecture
Important Links:
1.
2.
3.
Lecture No. / 6
Suggestion type / Adding definition of Data Dictionary
Artifact / Video lecture
Placement on Time Line / Page no. / 14:40:00

Data Dictionary:

A data dictionary is a file or a set of files that contains a database's metadata. The data dictionary contains records about other objects in the database, such as data ownership, data relationships to other objects, and other data.
The data dictionary is a crucial component of any relational database. Ironically, because of its importance, it is invisible to most database users. Typically, only database administrators interact with the data dictionary.
Lecture No. / 6
Suggestion type / Freestanding data dictionary description
Artifact / Video lecture
Placement on Time Line / Page no. / 15:55 :00– 16:50:00
Freestanding Data Dictionary:
A data dictionary that is a separate part of DBMS (non-integrated data dictionary) is referred to as freestanding data dictionary. It may be a commercial product or a simple file developed and maintained by a database designer. The freestanding data dictionary is useful in the initial stage of design for collecting and organizing information about data.
Lecture No. / 6
Suggestion type / Important web link for the current Lecture.
Artifact / Video lecture
Placement on Time Line / Page no. / 38:00:00

Lecture No. / 7
Suggestion type / Entity definition
Artifact / Video lecture
Placement on Time Line / Page no. / 3:16 – 5:55:00
Anentityis a thing or object of importance about which data must be captured. All things aren't entities, only those about which information should be captured.
Information about an entity is captured in the form of attributes and/or relationships. If something is a candidate for being an entity and it has no attributes or relationships, it isn't an entity.
Database entities appear in a data model as a box with a title. The title is the name of the entity.
Lecture No. / 7
Suggestion type / Entity description
Artifact / Video lecture
Placement on Time Line / Page no. / 16:00:00
External entity: Anything that receives or generates data from or to the system is an external entity, this term is normally used in data flow diagram.
Entity Type: Where as entity type is name assigned to a collection of properties of different things existing in an environment, this term is used in the context of ERD.
Lecture No. / 7
Suggestion type / New concept added
Artifact / Video lecture
Placement on Time Line / Page no. / 17:00:00
Entity with single instance is not represented in ER Diagram; this concept is missing in video lectures. So below contents should be added at interval 17:00
“Things with a single instance are not explicitly identified as entity type, so they are not represented in the E-R diagram. For example, a librarian is a single instance in a library system, that plays certain role in the library system and at many places data is generated from or to the librarian, so it will be represented at relevant places in the DFDs. But the librarian will not be explicitly represented in the E-R diagram of the library system”
Lecture No. / 8
Suggestion type / Significance of keys
Artifact / Video lecture
Placement on Time Line / Page no. / 07:00:00

Significance of Keys:

Keys are crucial to a table structure for the following reasons:
Keys ensure that each record in a table is precisely identified.As you already know, a table represents a singular collection of similar objects or events. (For example, a CLASSES table represents acollectionof classes, not just a single class.) The complete set of records within the table constitutes the collection, and each record represents a unique instance of the table's subject within that collection. You must have some means of accurately identifying each instance, and a key is the device that allows you to do so.
Keys help establish and enforce various types of integrity.Keys are a major component of table-level integrity and relationship-level integrity. For instance, they enable you to ensure that a table has unique records and that the fields you use to establish a relationship between a pair of tables always contain matching values.
Lecture No. / 8
Suggestion type / Identification of key attribute
Artifact / Video lecture
Placement on Time Line / Page no. / 12:30:00
While defining entity type, key attribute should be identified.
Lecture No. / 8
Suggestion type / Concept added
Artifact / Video lecture
Placement on Time Line / Page no. / 20:30 – 27:30:00
A Super key and composite key are similar to one another. Both of them are used to uniquely identify a row in a database table.
A super key is a set of columns within a table that can be used to identify a particular row in a table. A super key can be only one column or a combination of multiple columns. If a super key contains multiple columns it becomes a composite key.
Lecture No. / 8
Suggestion type / Concept explanation and example added
Artifact / Video lecture
Placement on Time Line / Page no. / 31:32 – 33:00:00
Candidate Key
A candidate is a subset of a super key. A candidate key is a single field or the least combination of fields that uniquely identifies each record in the table. The least combination of fields distinguishes a candidate key from a super key. Every table must have at least one candidate key but at the same time can have several.
As an example we might have a student_id that uniquely identifies the students in a student table. This would be a candidate key. But in the same table we might have the student’s first name and last name that also, when combined, uniquely identify the student in a student table. These would both be candidate keys.
Lecture No. / 9
Suggestion type / Concept added
Artifact / Video lecture
Placement on Time Line / Page no. / Interval: 13:30:00
Entities enrolled in a relationship are called its participants. The participation of an entity in a relationship is total when all entities of that set might be participant in the relationship otherwise it is partial e.g. if every Part is supplied by a Supplier then the SUPP_PART relationship is total. If certain parts are available without a supplier than it is partial.
Lecture No. / 10
Suggestion type / New slide added
Artifact / Video lecture
Placement on Time Line / Page no. / 35:00:00
Identifier Dependency:
It means that the dependent entity in case of existence dependency does not have its own identifier and any external identifier is used to pick data for that entity. And to define a key in this entity the key of the parent entity is to be used in the key for this entity may be used as composite keys.
Lecture No. / 11
Suggestion type / Missing Diagram
Artifact / Video lecture
Placement on Time Line / Page no. / 8:30 – 11:35 :00

Subtypes hold all the properties of their corresponding super-types. Means all those subtypes which are connected to a specific supertype will have all the properties of their supertype.
The Figure shows that the supertype and subtype relation between the SALARIED and HOURLY employees with the supertype entity EMPLOYEE, we can see that the attributes which are specific to the subtype entities are not shown with the supertype entity. Only those attributes are shown on the supertype entity which are to be inherited to the subtypes and are common to all the subtype entities associated with this supertype. The example shows that there is a major entity or entity supertype name EMPLOYEE and has a number of attributes. Now that in a certain organization there can be a number of employees being paid on different payment criteria.
Lecture No. / 12
Suggestion type / Modification/Missing module name
Artifact / Video lecture
Placement on Time Line / Page no. / 23:00
The heading “Subject registration” should add in the slides at interval 23:00. The lecturer explaining the example of three main modules of DFD with the help of the diagram but the slide contains no heading on it. It could be better to place names along with a diagram for the understanding of students that what module; the lecturer is explaining.
Lecture No. / 12
Suggestion type / Modification/Missing module name
Artifact / Video lecture
Placement on Time Line / Page no. / 27:05
The headings “Result submission” should add in the slides at the interval 27:05. The lecturer explaining the example of three main modules of DFD with the help of the diagram but the slide contains no heading on it.
Lecture No. / 12
Suggestion type / Modification/Missing module name
Artifact / Video lecture
Placement on Time Line / Page no. / 28:25
The headings “Result calculation” should add in the slides at the interval 28:25. The lecturer explaining the example of three main modules of DFD with the help of the diagram but the slide contains no heading on it.
Lecture No. / 14
Suggestion type / Missing Table/ Difference
Artifact / Video lecture
Placement on Time Line / Page no. / 2:15 – 2:58
“Difference between conceptual database design and logical database design” table is missing in video lecture which is present in handouts.
Conceptual Database Design / Logical Database Design
1 / Developed in a semantic data model (generally E-R data model) / In legacy data models (relational generally in current age)
2 / Free of data model in which going to be implemented; many/any possible / Free of particular DBMS in which going to be implemented; many/any possible
3 / Results from Analysis Phase / Obtained by translating the conceptual database design into another data model
4 / Represented graphically / Descriptive
5 / More expressive / Relatively less expressive
6 / Going to be transformed and then implemented / Going to be implemented
Lecture No. / 14
Suggestion type / Missing Definition –data model
Artifact / Video lecture
Placement on Time Line / Page no. / 2:50 – 4:15:00
Data model definition is missing. Definition and some general discussion on data model for concept clarity are necessary.
Data model is a set or collection of construct used for creating a database and producing designs for the databases.
The conceptual database design can be transformed into any data model, like, hierarchical, network, relational or object-oriented.
Lecture No. / 14
Suggestion type / Missing concept
Artifact / Video lecture
Placement on Time Line / Page no. / Interval: 03:00:00
The advantages of relational data model are given in handouts at page no 115, but it is not discussed in video lecture. The advantages of relational data model should also be given in video lecture at interval 03:00.
relational data model has a strong mathematical foundation that gives many advantages, like:
  • Anything included/defined in RDM has got a precise meaning since it is based on mathematics, so there is no confusion.
  • If we want to test something regarding RDM we can test it mathematically, if it works mathematically it will work with RDM (apart from some exceptions).
  • The mathematics not only provided the RDM the structure (relation) but also well defined manipulation languages (relational algebra and relational calculus).
  • It provided RDM certain boundaries, so any modification or addition we want to make in RDM, we have to see if it complies with the relational mathematics or not. We cannot afford to cross these boundaries since we will be losing the huge advantages provided by the mathematical backup.

Lecture No. / 15
Suggestion type / Insufficient explanation / detail
Artifact / Video lecture
Placement on Time Line / Page no. / 32:30 - 33:40
The respected instructor did not explain the concept of Null constraints, default value and Domain constraint sufficiently. There should be proper explanation of such a important concepts.
A Null value of an attribute means that the value of attribute is not yet given, not defined yet. It can be assigned or defined later however. Through Null constraint we can monitor whether an attribute can have Null value or not.
Default value constraint means that if we do not give any value to any particular attribute, it will be given a certain (default) value. This constraint is generally used for the efficiency purpose in the data entry process.