Entity Relationship Diagrams (ERDs) are conceptual data models used in software engineering to model information systems. ERDs represent entities as rectangles, attributes as ellipses, and relationships as diamonds connecting entities. Attributes can be single-valued, multi-valued, composite, or derived. Relationships have cardinality like one-to-one, one-to-many, many-to-one, or many-to-many. Participation constraints and Codd's 12 rules of relational databases are also discussed in the document.
Data modeling is a process used to define and analyze data requirements needed to support the business processes within the scope of corresponding information systems in organizations.
Data modeling is a process used to define and analyze data requirements needed to support the business processes within the scope of corresponding information systems in organizations.
You can get clear knowledge about the functional dependencies in "Normalization". And also the rules, types of FDs and finally the closure and its applications
You can get clear knowledge about the functional dependencies in "Normalization". And also the rules, types of FDs and finally the closure and its applications
Sarah Westlake, senior editor at MS Society talked about improving processes the MS Society used to have to identify case studies, and the brilliant new database being developed. She explained how they got started, who they got involved, and what they have learned along the way so far.
An overview of ER-diagrams including entity sets, relationship sets, and attributes. The four attributes types are covered and cardinality constraints. Further partial or full participation is discussed.
Download at http://DavidHubbard.net/powerpoint - This Introduction to Business Intelligence gives an overview of how Business Intelligence fits into business strategy in general. It does not go into the specific technologies of Business Intelligence. It is meant to be used to explain Business Intelligence to those not already familiar with Business Intelligence.
Relational data base management system (Unit 1)Ismail Mukiibi
Introduction to Relational database management system, A definition of an RDBMS is a DBMS in which data is stored in tables and the relationships among the data are also stored in tables. The data can be accessed or reassembled in many different ways without having to change the table forms.
https://www.learntek.org/blog/types-of-databases/
Learntek is global online training provider on Big Data Analytics, Hadoop, Machine Learning, Deep Learning, IOT, AI, Cloud Technology, DEVOPS, Digital Marketing and other IT and Management courses.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
2. ER diagrams
• ER-modeling is a data modeling technique used in software
engineering to produce a conceptual data model of a
information system.
• Diagrams created using this ER-modeling technique are called
Entity-Relationship Diagrams, or ER diagrams or ERDs.
3. Entity
• Entities are represented by means of rectangles.
Rectangles are named with the entity set they
represent.
Entities in a school database
4. Attributes
• Attributes are properties of entities. Attributes are
represented by means of eclipses. Every eclipse represents
one attribute and is directly connected to its entity
(rectangle).
5. composite attributes
• If the attributes are composite, they are further divided in a
tree like structure. Every node is then connected to its
attribute. That is composite attributes are represented by
eclipses that are connected with an eclipse.
8. Relationship
• Relationships are represented by diamond shaped
box. Name of the relationship is written in the
diamond-box. All entities (rectangles), participating
in relationship, are connected to it by a line.
9. Binary relationship and cardinality
• A relationship where two entities are participating, is
called a binary relationship.
• Cardinality is the number of instance of an entity
from a relation that can be associated with the
relation.
10. One-to-one
• When only one instance of entity is associated with the
relationship, it is marked as '1'. This image below reflects that
only 1 instance of each entity should be associated with the
relationship. It depicts one-to-one relationship
• The 1:1 (read as “one to one”) relationship means that one
instance of the parent entity is associated with one instance
of the child entity.
Example: Employee of the month and parking for him.
11. One-to-many
• When more than one instance of entity is associated with the relationship,
it is marked as 'N'. This image below reflects that only 1 instance of entity
on the left and more than one instance of entity on the right can be
associated with the relationship. It depicts one-to-many relationship
• In this kind of relationship, a single instance of a parent entity is
associated with many instances of a child entity; however, the child entity
instance is related to only one instance of the parent.
Example:
12. Many-to-one
• When more than one instance of entity is associated with the relationship,
it is marked as 'N'. This image below reflects that more than one instance
of entity on the left and only one instance of entity on the right can be
associated with the relationship. It depicts many-to-one relationship.
• In this case, many instances of a parent entity can relate to many instances
of a child entity.
13. Many-to-many
• This image below reflects that more than one instance of
entity on the left and more than one instance of entity on the
right can be associated with the relationship. It depicts many-to-
many relationship
14. Participation Constraints
• Total Participation: Each entity in the entity is involved in the
relationship. Total participation is represented by double
lines.
• Partial participation: Not all entities are involved in the
relation ship. Partial participation is represented by single line.
15. Codd's 12 Rules
• Dr Edgar F. Codd did some extensive research in Relational Model of database
systems and came up with twelve rules of his own which according to him, a
database must obey in order to be a true relational database.
• These rules can be applied on a database system that is capable of managing is
stored data using only its relational capabilities. This is a foundation rule, which
provides a base to imply other rules on it.
• Rule 1: Information rule: This rule states that all information (data), which is
stored in the database, must be a value of some table cell. Everything in a
database must be stored in table formats. This information can be user data or
meta-data.
• Rule 2: Guaranteed Access rule: This rule states that every single data element
(value) is guaranteed to be accessible logically with combination of table-name,
primary-key (row value) and attribute-name (column value). No other means, such
as pointers, can be used to access data.
• Rule 3: Systematic Treatment of NULL values: This rule states the NULL values in
the database must be given a systematic treatment. As a NULL may have several
meanings, i.e. NULL can be interpreted as one the following: data is missing, data
is not known, data is not applicable etc.
16. • Rule 4: Active online catalog: This rule states that the structure description of
whole database must be stored in an online catalog, i.e. data dictionary, which can
be accessed by the authorized users. Users can use the same query language to
access the catalog which they use to access the database itself.
• Rule 5: Comprehensive data sub-language rule :This rule states that a database
must have a support for a language which has linear syntax which is capable of
data definition, data manipulation and transaction management operations.
Database can be accessed by means of this language only, either directly or by
means of some application. If the database can be accessed or manipulated in
some way without any help of this language, it is then a violation.
• Rule 6: View updating rule: This rule states that all views of database, which can
theoretically be updated, must also be updatable by the system.
• Rule 7: High-level insert, update and delete rule: This rule states the database
must employ support high-level insertion, updation and deletion. This must not be
limited to a single row that is, it must also support union, intersection and minus
operations to yield sets of data records.
• Rule 8: Physical data independence: This rule states that the application should
not have any concern about how the data is physically stored. Also, any change in
its physical structure must not have any impact on application.
17. • Rule 9: Logical data independence: This rule states that the logical data must be
independent of its user’s view (application). Any change in logical data must not
imply any change in the application using it. For example, if two tables are merged
or one is split into two different tables, there should be no impact the change on
user application. This is one of the most difficult rule to apply.
• Rule 10: Integrity independence: This rule states that the database must be
independent of the application using it. All its integrity constraints can be
independently modified without the need of any change in the application. This
rule makes database independent of the front-end application and its interface.
• Rule 11: Distribution independence: This rule states that the end user must not be
able to see that the data is distributed over various locations. User must also see
that data is located at one site only. This rule has been proven as a foundation of
distributed database systems.
• Rule 12: Non-subversion rule: This rule states that if a system has an interface that
provides access to low level records, this interface then must not be able to
subvert the system and bypass security and integrity constraints.