MS SQL SERVER: Introduction To Database Concepts
- 1. 1SQL SERVER: AN INTRODUCTION TO DATABASE CONCEPTS
- 2. What is Data?Data is any fact or statistic which can be operated on to derive meaningful information. It is a raw fact.Simply put:Data is any raw factEg: Size = 12 is data Name = ‘Dennis’ is another data We cannot derive conclusions directly from the data without processing themExample of a Data
- 3. Why is Data important? Data is important because every decision that happens in the world is based on some data
- 4. For example, if Jenny wants to buy a laptop, she needs the right data to make appropriate decision on the model. Like its cost, market value, etc.
- 5. Hence, every decision depends on the data corresponding to itWHICH SHALL I BUY? Cost = $360Cost = $450
- 6. Data in real-world In the real world, data has become ubiquitous, i.e, data is every-where
- 7. All aspects of the modern business and domestic life-styles feed of huge amounts of data
- 8. The Amount of data is increasing exponentially and we needed a flexible, reliable and secure way to organize this data.
- 9. That is where Databases came to our rescue! What is a Database A Database is a collection of interrelated data
- 10. For example:
- 11. A Database on students may contain the names, rollnumbers and GPAs of students in a university
- 12. A Zoo database may contain the names, RFID tag numbers, weights and ages of animals in a zoo
- 13. The List goes on
- 14. What is so special about a database? Why can’t we just use files? (like text files and word documents). The Next slide answers this Qn.
- 15. Problems with filesInconsistency In a system, a user may use different applications and these may use different formats of data. Hence, interoperability between their data is difficultFor Example: Willy, Tim and Rose have been asked to write an essay on MJ, and they use different platforms, they’d have difficulty combining the Data into a single-final document: IncompatibiltyXWilly Uses MicrosoftWordTim Uses WordStarRoseUses Mellel, a Word processor for Macintosh systems
- 16. Problems with filesData RedundancyWhen handling large amount of data, there might be recurrences of data in case of files. This wastes memory space.Integrity The data is susceptible to corruption due to system failuresConcurrent Access anomaliesWhen many people try to write a piece of data concurrently – we’ll have problems in case of filesSecurity problemIll minded people may get access to our files if they are not secured properly.
- 17. Applications of DBMS in real lifeThe DBMS stands for: Database Management SystemDBMS is a collection of related data (a database) and programs which allow users to work on that data (the management system)DBMS eliminates the various problems that are associated with file storagesIn real-life, DBMS have a wide spectrum of applications: In Movie theatres for holding ticket reservation details
- 18. In Prisons for managing info about the prisoners
- 19. In Banks, to manage customer and account infoDatabase FeaturesA Database consists mainly of TablesA Table is a set of values that is organized using a model of vertical columns (which are identified by their name) and horizontal rows. A Table has a specified number of columns, but can have any number of rows. Each row is identified by the values appearing in a particular column subset which has been identified as a candidate key.Let’s take an example
- 20. Database FeaturesExampleConsider a database for the dreams that ‘George’ had this week. It has a table called ‘History’ where he stores the date and time at which he dreamt. This table will look as follows:An ‘ATTRIBUTE’ which can uniquely identify a record in a table is called a ‘KEY’. Eg: Dream NumberThe ‘TYPE’ of data is called as ‘ATTRIBUTE’ or ‘FIELD’. Eg: Date, Time,etcThe ‘VALUES’ of a set of attributes, which define a unique object is a ‘RECORD’
- 21. SummaryDatabase ConceptsData is a fact
- 23. Database is a collection of related data
- 24. DBMS is used to manage database
- 25. Usage: Anyplace where data are concerned
- 26. A Database consists mainly of Tables
- 27. A Table consists of: Records (Rows in a table)Attributes (Columns in a table)Keys (Used to uniquely identify a record in a table)End
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