2.2.1 RELATIONAL ALGEBRA
Relational algebra is a set of operators used to perform operations on tables. Operators in Relational Algebra takes one or more tables as parameters and produce one table as the result (Sharma, R. 2013).
The following are operators in “Relational Algebra”:
• Union - takes two tables, and returns all rows that are belonging to: both tables or, either first table or either second table.
• Intersect - takes two tables, and returns all rows that are belonging only to the first table and to the second table.
• Difference/Minus - takes two tables, and returns all rows that exist only in the first table, not in the second one.
• Project - takes a single table, and returns the “vertical subset” of the table.
• Select
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So, rows of two table are combined, based on given column values (Sharma, R. 2013).
2.2.2 STRUCTURED QUERY LANGUAGE (SQL)
SQL stands for Structured Query Language, is the standard language used in all relational database management systems for data manipulation and retrieval (Tomar, N. 2013). Structured Query Language is a “non-procedural language”, where you need to concentrate on: “What you want” not on “How you get it”, in other words you do not need to be concerned with procedural details.
Depending upon what they do, SQL Commands are divided into four categories:
DDL (Data Definition Language), commands such as CREATE is used to define the data.
DML (Data Manipulation Language), commands such are INSERT and DELETE are used to manipulate data.
DCL (Data Control Language), commands such is GRANT is used to control access to data.
Query (Retrieving data), is used to retrieve data using SELECT command.
2.2.3 PROCESSING
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For example: two departments contain their own system for their own data processing needs, where each of them stores data and runs all programs related to them. The biggest problem of decentralized data processing method is that: “data is to be duplicated”. Since common data is to be stored in each machine (redundancy), will cause data inconsistency. This means that data stored by two departments will not agree with each other (data will be duplicated), because there is no means to store common data in one place and access from all machines (Sharma, R.
Throughout the second half of this semester, dual relationships have been emphasized as one of the most frequently encountered ethical dilemmas faced by behavior analysts in the field today. According to the class lectures, assigned text, and other articles that we have read, this is due to the fact that we interact with our clients and those caring for them in their natural settings. As a result, those we provide services to, and interact with, are in the places in which they feel the most comfortable, their homes or regular classrooms. This is in stark contrast to a formal office setting, which projects an atmosphere with both expected standards of acceptable behavior, and clear boundaries between client and the service provider. In an effort
Command XML consists of commands that the database needs to carry out. It also contains user name and password for authentication purpose.
In understanding Relational Cultural Theory (RCT), we will first examine its fundamental assumptions and then critically assess those assumptions. Next, we will evaluate RCT’s assumptions to determine its relevance to the core values of social work. Finally, we will determine the ways RCT can best guide social work practice.
In this paper, I am going to use concepts from the social exchange theory and relational dialectics theory to describe my relationship with my boyfriend. First, I will discuss the cost and rewards of the relationship. Second, I will then discuss the dialectics of autonomy and connection followed by, openness and protection.
Being a nurse and belonging to nursing society is not easy and it requires a lot of hard work and also for individuals to have some outstanding characters in order to be successful. As for me, the thing I find in common with me and nursing is that I’m compassionate, Honest, and have self-confidence; To me those are some key elements one need to have in order to fit in the nursing society and in this essay I will be explaining how those key elements relate me to the nursing society.
The connection-autonomy dialectic is the dialectical tension that I have found to be most challenging in my relationships, especially in my friendships, or lack of them. Finding a balance on the spectrum of these two has always been harder for me and is something that I continue to struggle with. I would say that my entire life I have fallen more on the autonomy side of this dialectical continuum. When I was younger I just thought I was shy, but as I have gotten older and explored my personality, I have realized that I am just very introverted and would really rather be alone. It is kind of depressing to say, but my social life consists of my retail job because after all that interaction I am just drained
Introduction: Thoughts from the Breakroom The coffee has gotten cold, the soggy sandwich you brought for lunch is suddenly unappealing, and the conversation has run stale. The clock could not possibly be moving any slower. Your cubicle buddy is busy working on his customer reports, your boss is locked away in his office, and the creepy dude that sits that stares at you from his desk so happens to be taking his lunch break at the same time as you.
have this need to relate the table to each you can see how I am going
[7] Elmasri & Navathe. Fundamentals of database systems, 4th edition. Addison-Wesley, Redwood City, CA. 2004.
A database is a structured collection of data. Data refers to the characteristics of people, things, and events. Oracle stores each data item in its own field. For example, a person's first name, date of birth, and their postal code are each stored in separate fields. The name of a field usually reflects...
It was introduced to alleviate the data-dependency problem and also to remove unnecessary burdens from the application programmer. Some DBMS examples include mysql, postgresql, Microsoft Access, SQL Server, filemaker, Oracle, RDBMS, dbase, Clipper, and foxpro. It is important for there to be a way for them to communicate with each other since there are so many database management systems available. In database management systems, data is available in three levels which is physical level, conceptual level, and user ...
Throughout most of my life I have gained friendships and relationships with others that have turned into long term, but others which only lasted a short while. The friendship that has greatly impacted my life significantly over the last eight years is someone who means so much to me. This meaningful friendship all started back when I was in middle school, which has grown stronger over the years. I met Brooke in middle school because we had some of the same classes and were in homeroom together. Our friendship developed quickly and lasted throughout our high school years. We became really close our Junior and Senior year of high school. But, maintaining our friendship hasn’t always been so easy. Today, we text and call each other on our free time, but I know I can count and rely on her when I need someone to talk too. I call her my second sister and vice versa. And when we go home on breaks we see one another as much as we can. The best part of our relationship is that if one is in need of advice or in need of a shoulder to cry on, we are always there for one another. Keeping in contact is very important in our relationship and communication has played a key role in our relationship.
PL/SQL supports both static and dynamic SQL. Static SQL supports DML operations and transaction control from PL/SQL block. Dynamic SQL is SQL allows embedding DDL statements in PL/SQL blocks.
“Relationships are what make up our world today, they shape the ways we see things and the way that we do things, relationships affect how we see the world today”. I believe supporting what your partner does, having a great sum of trust and showing your affections towards your partner is what will make a healthy relationship great.
The idea and development of relationships was always very black and white for me. I had always seen all relationships such as friendships, partnerships, and family relationships, falling under one category. I have recently learned this is not the case at all. There are actually many different components that make up a relationship and as well different categories for different relationships. Robert Sternberg created a model of love called the triangular model of relationships that encompasses the various elements that are necessary for any relationship and as well the different classifications of relationships (Brannon, 2011). In his model, there are three components that make up the triangle.