Advantages of a dbms

Using a DBMS to store and manage data comes with advantages, but also overhead. One of the biggest advantages of using a DBMS is that it lets end users and application programmers access and use the same data while managing data integrity. Data is better protected and maintained when it can be shared using a DBMS instead of creating new iterations of the same data stored in new files for every new application. The DBMS provides a central store of data that can be accessed by multiple users in a controlled manner.

Central storage and management of data within the DBMS provides:

• Data abstraction and independence

• Datasecurity

• A locking mechanism for concurrent access

• An efficient handler to balance the needs of multiple applications using the same data

• The ability to swiftly recover from crashes and errors, including restartability and recoverability

• Robust data integrity capabilities

• Logging and auditin go factivity

• Simple access using a standard application programming interface (API)

• Uniform administration procedures for data

Another advantage of a DBMS is that it can be used to impose a logical, structured organization on the data. A DBMS delivers economy of scale for processing large amounts of data because it is optimized for such operations.

A DBMS can also provide many views of a single database schema. A view defines what data the user sees and how that user sees the data. The DBMS provides a level of abstraction between the conceptual schema that defines the logical structure of the database and the physical schema that describes the files, indexes and other physical mechanisms used by the database. When a DBMS is used, systems can be modified much more easily when business requirements change. New categories of data can be added to the database without disrupting the existing system and applications can be insulated from how data is structured and stored.

Of course, a DBMS must perform additional work to provide these advantages, thereby bringing with it the overhead. A DBMS will use more memory and CPU than a simple file storage system. And, of course, different types of DBMSes will require different types and levels of system resources.

Database model is a type of data model that determines the logical structure of a database and fundamentally determines in which manner data can be stored, organized, and manipulated. The most popular example of a database model is therelational model, which uses a table-based format.

Types of databases

1.A document-oriented database is a computer program designed for storing, retrieving, and managing document-oriented, or semi structured data, information

Document-oriented database

2.Embedded database. These databases consist of data developed by individual end-users. Examples of these are collections of documents, spreadsheets, presentations, multimedia and other files.

3. Graph database is a kind of No SQL database that uses graph structures with nodes, edges, and properties to represent and store information.

4.Hypertext databases are particularly useful for organizing large amounts of disparate information. For example they are useful for maintaining online encyclopedias.

5.Hypertext database

6.Operational database. These database store detailed data about the operations of an organization.

7. A distributed database is a database in which storage devices are not all attached to a common processing unit such as the CPU. It may be stored in multiple computers located in the same physical location, or may be dispersed over a network of interconnected computers.

8.Flat-File. The flat-file style of database are ideal for small amounts of data that needs to be human readable or edited by hand

• The difference between data and information

• What a database is, what the different types of databases are, and why they are valuable assets for decision making

• The importance of database design

• How modern databases evolved from file systems

• About flaws in file system data management

• What the database system’s main components are and how a database system differs from a file system

• The main functions of a database management system (DBMS)

№6 Lecture

• Data Analysis.

• Data management.

• Fundamentals of data analysis. collection methods, classification and prediction.

• Decision trees. Handling arge amounts of data.

• Methods and Data Mining stage.

• Data Mining Tasks.

• Data Visualization.

Data analysis is the process of developing answers to questions through the examination and interpretation of data.

The Excel - one of the most popular data analysis tools, to help visualize and gain insights from your data.

Microsoft Excel 2007 is an electronic spreadsheet software package that allows you to organize data in a tabular format, perform mathematical calculations, and analyze data. This software includes functions, formulas, and charts. It is commonly used in business, engineering, mathematics, and statistics.

Microsoft Excel is one of the most used software applications of all time. Hundreds of millions of people around the world use Microsoft Excel. You can use Excel to enter all sorts of data and perform financial, mathematical or statistical calculations.

Microsoft Excel records cell addresses in formulas in three different ways, called absolute, relative, and mixed.

Excel has to offer to analyze data.

1 Sort:

2 Filter:

3. Conditional Formatting:

4 Charts:

5 Pivot Tables:

6 Tables:

7 What-If Analysis:

8 Solver:

9 Analysis ToolPak:

1 Sort: You can sort your Excel data on one column or multiple columns. You can sort in ascending or descending order.

2 Filter: Filter your Excel data if you only want to display records that meet certain criteria.

3. Conditional Formatting: Conditional formatting in Excel enables you to highlight cells with a certain color, depending on the cell's value.

4 Charts: A simple Excel chart can say more than a sheet full of numbers. As you'll see, creating charts is very easy.

Create a Chart

To create a line chart, execute the following steps.

1. Select the range A1:D7.

2. On the Insert tab, in the Charts group, choose Line, and select Line with Markers.

5 Pivot Tables: Pivot tables are one of Excel's most powerful features. A pivot table allows you to extract the significance from a large, detailed data set.

Our data set consists of 214 rows and 6 fields. Order ID, Product, Category, Amount, Date and Country.

6 Tables: Tables allow you to analyze your data in Excel quickly and easily.

To insert a table, execute the following steps.

1. Click any single cell inside the data set.

7 What-If Analysis: What-If Analysis in Excel allows you to try out different values (scenarios) for formulas.

What-If Analysis in Excel allows you to try out different values (scenarios) for formulas. The following example helps you master what-if analysis quickly and easily.

Assume you own a book store and have 100 books in storage. You sell a certain % for the highest price of $50 and a certain % for the lower price of $20.

8 Solver: Excel includes a tool called solver that uses techniques from the operations research to find optimal solutions for all kind of decision problems.

1. On the green File tab, click Options.

2. Under Add-ins, select Solver Add-in and click on the Go button.

9 Analysis ToolPak: The Analysis ToolPak is an Excel add-in program that provides data analysis tools for financial, statistical and engineering data analysis.

1. Click on the green File tab. The File tab in Excel 2010 or later replaces the Office Button (or File Menu) in previous versions of Excel.

2. Click on Options.

3. Under Add-ins, select Analysis ToolPak and click on the Go button.

4. Check Analysis ToolPak and click on OK.

5. On the Data tab, you can now click on Data Analysis.

The following dialog box below appears.

6. For example, select Histogram and click OK to create a Histogram in Excel.