Computer class of agriculture production 5.pptx
- 1. What is Database? •A database is a systematic collection of data. •They support electronic storage and manipulation of data. •Databases make data management easy.
- 2. Types of Databases • Distributed databases • Relational databases • Object-oriented databases • Centralized database • Open-source databases • Cloud databases
- 4. • Hardware: The hardware consists of physical, electronic devices like computers, I/O devices, storage devices, etc. This offers the interface between computers and real-world systems. • Software: This is a set of programs used to manage and control the overall database. This includes the database software itself, the Operating System, the network software used to share the data among users, and the application programs for accessing data in the database.
- 5. • Data: Data is a raw and unorganized fact that is required to be processed to make it meaningful. Data can be simple at the same time unorganized unless it is organized. Generally, data comprises facts, observations, perceptions, numbers, characters, symbols, images, etc. • Procedure: Procedure are a set of instructions and rules that help to use the DBMS. It is designing and running the database using documented methods, which allows to guide the users who operate and manage it.
- 6. • Database Access Language Database Access language is used to access the data to and from the database, enter new data, update already existing data, or retrieve required data from DBMS. The user writes some specific commands in a database access language and submits these to the database.
- 7. What is a Database Management System (DBMS)? • Database Management System (DBMS) is a collection of programs that enable its users to access databases, manipulate data, report the data and delete the data from the database. • Charles Bachman's Integrated Data Store (IDS) is said to be the first DBMS in history represent data.
- 8. Advantages of DBMS •DBMS offers a variety of techniques to store & retrieve data. •DBMS serves as an efficient handler to balance the needs of multiple applications using the same data. •Uniform administration procedures for data. •Application programmers never exposed to details of data representation and storage. •Offers Data Integrity and Security. •The DBMS implies integrity constraints to get a high level of protection against prohibited access to data. •Reduced Application Development Time.
- 9. Disadvantage of DBMS • Cost of Hardware and Software of a DBMS is quite high which increases the budget of your organization. • Most database management systems are often complex systems, so the training for users to use the DBMS is required. • In some organizations, all data is integrated into a single database which can be damaged because of electric failure or database is corrupted on the storage media. • Use of the same program at a time by many users sometimes lead to the loss of some data. • DBMS can't perform sophisticated calculations.
- 10. RDBMS The software used to store, manage, query, and retrieve data stored in a relational database is called a relational database management system (RDBMS). The RDBMS provides an interface between users and applications and the database, as well as administrative functions for managing data storage, access, and performance.
- 11. Row In the context of a relational database, a row—also called a tuple—represents a single, implicitly structured data item in a table. Column A column can also be called an attribute. Each row would provide a data value for each column and would then be understood as a single structured data value. Table A table has a specified number of columns, but can have any number of rows. Each row is identified by one or more values appearing in a particular column subset.
- 12. Data Type A data type is an attribute that specifies the type of data that the object can hold: integer data, character data, monetary data, date and time data, binary strings, and so on. Char A FIXED length string (can contain letters, numbers, and special characters). The size parameter specifies the column length in characters - can be from 0 to 255. Default is 1. VARCHAR(size) A VARIABLE length string (can contain letters, numbers, and special characters). The size parameter specifies the maximum column length in characters - can be from 0 to 65535
- 13. INT(size) A medium integer. Signed range is from -2147483648 to 2147483647. Unsigned range is from 0 to 4294967295. The size parameter specifies the maximum display width (which is 255) FLOAT(size,d) A floating point number. The total number of digits is specified in size. The number of digits after the decimal point is specified in the d parameter. DOUBLE(size, d) A normal-size floating point number. The total number of digits is specified in size. The number of digits after the decimal point is specified in the d parameter
- 14. What Is Database Architecture? - The Database Management System (DBMS) architecture shows how data in the database is viewed by the users. It is not concerned about how the data are handled and processed by the DBMS. It helps in implementation, design, and maintenance of a database to store and organize information for companies. The architecture of DBMS can be defined at three levels as follows − External level/ View level Conceptual level/ logic level Internal level/ storage level
- 15. The levels in the architecture of DBMS are shown below in diagram form −
- 16. External level/ View level External level describes a part of the database that is relevant to each user. This level insulates the users from the details of conceptual and the internal level. Conceptual level/ logic level Conceptual level describes what data is stored into the database and the relationship among the data. It represents the following − All the entities, attributes and their relationships. The constraints on the data. Security and integrity information. Internal level/ storage level Internal level is the physical representation of the database on the computer. This level describes how the data is stored in the database. It covers the data structure and file organization used to store the data on storage devices.
- 17. 1-tier architecture: • One-tier architecture involves putting all of the required components for a software application or technology on a single server or platform. • Basically, a one-tier architecture keeps all of the elements of an application, including the interface, Middleware and back-end data, in one place. Developers see these types of systems as the simplest and most direct way.
- 18. 2-tier architecture: • The two-tier is based on Client Server architecture. • The two-tier architecture is like client server application. • The direct communication takes place between client and server. • There is no intermediate between client and server.
- 19. 3-tier architecture: • Database (Data) Tier − At this tier, the database resides along with its query processing languages. • Application (Middle) Tier − At this tier reside the application server and the programs that access the database. • User (Presentation) Tier- multiple views of the database can be provided by the application. All views are generated by applications that reside in the application tier.