Chapter 5

The chapter discusses the topics of what is database processing, why data processing is use and how data processing is use. The chapter starts by describing what’s the purpose of a database and its system components. Part of the sections in the chapters, shows how data models are used to design database structure. These database systems are used to solve problems and who knows where database technology will be in the future.

Q5-1 What Is the Purpose of a Database

Database are used to keep track of things, for example many professionals use spreadsheets to keep track of their inventory. Spreadsheets are used to keep track of a single theme, such as only the inventory. However, a database can be used to keep track of multiple tasks or items. Database can contain multiple themes, such as inventory, emails and tasks. These are both consider a general rule when it comes to the purpose of a database.

Q2: What Is a Database?

Self-describing collection of integrated records is called a database. A database consists of bytes, these characters of data. Bytes in a database are grouped into columns which can be also called fields. Records are grouped into rows and correlate with the fields. So the collection of data in these columns and rows, are grouped together into a table. Files are tables, that display’s the collection of data in both the fields and records. So the structure of the database is a collection of tables or files that correlate with the records and special data called metadata. These databases are sometimes stored on disks. Now the “among the relationship on rows” is where the rows of different tables correlate together. A unique row in one of these tables crosses over to a primary key, which is column or group of columns. These columns can be foreign keys that resides in a foreign table. Relational databases carry data in the form of tables and uses the relationship of foreign keys. Metadata in a database makes the database much more useful. Since the database can use the metadata to remember and record. Now the format of metadata relies on the software which processes the database.

Q5-3 What Is a Database Management System (DBMS)?

A database management systems are the programs creating, processing and administering a database. DMBS are not developed by any organizations and instead are licensed out to organizations from different vendors. A database management system is different from a database and is a software program.

Creating the Database and Its Structures

DBMS is use by database developers to create these tables, relationships and most structures in the database. The developer creates a new table; the metadata fills the table in the form.

Processing the Database

Processing the database is the 2^nd function to the database management system, which is complicated. However, the DBMS are the fundamentals and is using four different processing operations. These operations are to read, insert, modify or delete data. Database Management System rely on these operations, especially when the users either enter new or change the data.

Administering the Database

Now administering the database is the third function to the database management system. The database administration are assistant tools and include various activities to its database. For example, think of security when a user needs to log onto its account. These functions can include recovering past database data. Additionally, improving the structure, performance of database’s and removes unnecessary data.

Q5-4 How Do Database Applications Make Databases More Useful?

 Data in database tables are only useful when the information is conceptual and place in the correct forms. Specifically, there’re four elements of a database application program: forms, reports, queries, application programs. Traditionally databases are shared among many users and serve their purpose. The browser applications in a database are also shared among its users. These applications on the internet are thin-client applications, which aren’t pre-installed on those computers. So the applications forms, reports and queries run through javascipt and html codes. Besides traditional queries, graphical queries are criteria’s created when a user clicks on graphic displays.  Now, multi-user processing commonly does have problems that are difficult to understand. So make sure to be cautious and aware of these multi data conflicts.

Q5-5 How Are Data Models Used for Database Development?

There’re two topics being consider when it comes to database development, both data modeling and database design. The design of the model relies on the user involvement and business environment. Database developers must know what the user wants and what to include. Data models are constructed as database data in a logical representation. It represents the data and what it’s supposed to store in the database.

Entities

An entity is when user wants to track something and can represented in many variations. Attributes are part of entities because they describe the characteristics of the entity. An identifier is what recognizes an attribute’s value which is associated with only one entity.

Relationships

Each entity has a relationship to one another, for example: An “order” is related to a “customer” entity and a “salesperson” entity. So database designers use diagrams to show these type of relationships. Entity-relationship (E-R) diagrams where one type of all the entities are showed in a single rectangle. Lines are used to show the relationship between two separate entities, vertical bars to represent one type of entity and crow’s feet. Crow’s feet are shorthand for multiple lines between different entities and are in one-to-many relationships. Since these type of relationships has one entity correlating with multiple entities however going the other way around doesn’t work.  Many-to many relationships represent different entities that have relations between each other and correlate with other entities too. Crow’s-foot diagram shows the relationships of both maximum and minimum cardinalities.  Maximum cardinality is the maximum number of entities in a relationship. Vertical bar on a line means at least one entity required. Minimum cardinality is the minimum number of entities in a relationship. Small oval means entity is optional so the relationship does not need to have an entity of that type.

Q5-6 How Is a Data Model Transformed into a Database Design?

By converting a data model into tables, relationships and data constraints is what transforms into a database designed. There’re two kinds of database design concept, normalization and the representation of two kinds of relationships. Normalization is processing a poor constructed data table into two or more efficient tables. Since data integrity problems arise when a table is poorly managed and constructed; causing incorrect results.  Normalizing the table is using the various normal forms to take out duplicated data and other problems that could arise. So normalization is well constructed table and has only one type of theme. Representing relationships are turning a data model into a relational database design. Step 1 is to create a table for each entity then the identifier of the entity becomes normalize. Resulting in each table having a single theme and finally represent the relationship between the tables. The users’ role in the development of databases must thorough look through the data tables and devote the time to final judging.

Q5-8 2026?

So in the year 2026, it’s said the amount of databases will drastically increase. It will also have cheaper and unlimited storage in these databases which will have fast processing speeds. Then ACID transactions will come into play and are critical to original commercial applications. Either all of a transaction is processed or none of it is. Transactions are processed in the same manner whether processed alone or in the presence of millions of other transactions. Once a transaction is stored it never goes away, even in the presence of failure. There’ll be new categories of DMBS, such as NotRelational DBMS which supports high transaction rates and processes simple data structures. NewSQL DBMS processes higher level transactions and provide ACID support. Last, In-memory DBMS uses high volume ACID transactions which have complex relational query processing.