- What is a Relational Database? Explain also (1a) what are relational tables? (1b) the primary key? (1c) the foreign key? (1d) normalization? (1e) SQL query language?
Answer. Relational database means a structured data organized in the form of “Tables” from where data can be accessed with information already stored. Table relationships are used to join tables when we need database object. Table relationship can match data in key columns. It matches the primary key in one table. In relational data, Primary key is always a unique key for example a telephone number or a green card number. The relational database can use only one unique primary key. A Foreign key is a key that refers to the Primary key in the first table and foreign itself is defined in the second table which contains one or a set of fields in a single table identifying the other table. Database normalization is the process of improving the integrity of data and reduction in redundancy of data and involved in organizing relations with columns. SQL query language is a special language to manage, relate, modify and access data in data relationship. This language is to help to insert, delete, update, the data from a database.
- What are the major capabilities of Data Base Management System (DBMS)? And why is a Relational DBMS is the most prevalent type of database software in the business world?
Answer. Data Base Management System is based on four major points. These four types are Data Structure, Transaction mechanism, modeling language and database query. The capabilities of database management system are Replication and Backup of data, Computation of date, Query ability, Rule Enforcement and Security.
Replication and backup mean It creates a copy of attributes on a regular basis and in the case where disks are failed it provides the backup and replace the data. On the attributes there are some computations like cross referencing, grouping, summing, sorting, counting and averaging. Instead of implementing this from the beginning database management system is used to provide these calculations. Query ability is the ability to answer the questions asked by the person to the computer; DBMS is used to answer these questions and answer these very quickly. Rule enforcement is used in DBMS this is the main capability of the database management system. It helps businesses to provide them security and it is also less time-consuming software.
- What are data warehouses? What are Data Marts? How they different from databases?
Answer. Database Warehouses is based on the capture the data from different sources to analyze and to access the data. Sometimes the end user needs to access the local or special database but it did not provide this facility to the end user. Two approaches are being used to access database warehousing. First, one is top down approach and the second one is bottom up approach. The first approach is used when the warehouse data is created and this is used for the users of specific groups this approach spins Data Mart for them. These are different from database management system as they use a specific server. Data is extracted selectively from the applications used and the online data transactions processing.
- What is Hadoop? What types of applications are suitable for Hadoop?
Answer. Hadoop is used for running different applications on different hardware; Hadoop is used for storing data is a source that is open for the software framework. Hadoop provides a very big space to store the data of any kind. It can perform different numerous jobs and tasks at the same time. Hadoop can process and handle a large amount of data at the same time. Map Reduce programming is an application used for the Hadoop. That is an application which is used to tackle the problems of accessing the data. Applications that are used to access the data and can response the query of the user can be used in Hadoop. It can also support real-time ad-hoc of express and the data aggregation.
- We are in an era of big data. To extract Business Intelligence from big data, an array of tools are used today. Describe what are OLAP and Data Mining and what are the purposes of these tools.
Answer. OLAP is the abbreviation of Online analytic processing it is a processing of computers and laptops to extract and analyze the data to view it by the user. A multidimensional database is a place where the OLAP data is saved. Whereas the Data mining is a discovering knowledge it is being used to analyze date and process the data for many reasons and make it a useful and understandable information for the user of this data. It is also considered as a tool to analyzes date for example to cut the cost of to increase the revenue of the company. It can find patterns and correlations from the different fields in the large relational database.
- Explain what are text mining and web mining? What are their benefits?
Answer. Text mining is based on text that is using words to insight the business, and it helps the business to grow well. Text mining can be through facebook or twitter or any other application and also through e.mails and text messages. Whereas the Web mining is used to look for the activities in the data. This search can be through usage mining, structure mining, and content mining. Web mining is used to gather the data of users either through forms submitted by the user or data which is used during the web transactions. Text mining has many benefits that include the cost saving for the business or any activity for which the text mining has been performed. It is also beneficial for the innovation of new services for example for new medical treatment and the productivity gains. However, web mining is beneficial and a good source for the knowledge of students and business as well.