Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Explain the concept of QBE?
Query-by-example represents a visual/graphical approach for accessing information in a database by the use of query templates called as skeleton tables. It is used through entering example values directly within a query template to represent what is to be achieved. QBE was developed at IBMs. T.J. Watson Research Centre and it is used through many database systems for personal computers. QBE is an extremely powerful facility that gives the user the capability to access the information a user needs without the knowledge of any programming language.
Queries in QBE are expressed through skeleton tables. QBE has two distinct features:
- QBE has two-dimensional syntax: Queries look like tables.- QBE queries are expressed "by example". Instead of giving a process for obtaining the desired answer, the user provides an example of what is desired.An example of QBE is given asEMPNO NAME SALARY DESIG DEPTNO P..x "Manager"
This query tells the system to such as for tuples in EMP relation which have designation Manager. For each such tuple, the system assigns the value of the Ename attribute to the variable x and prints it.
You have a friend that runs a motor bike club that holds racing events at various venues on weekends, on a monthly basis. Some venues are private race tracks and some are dirt trac
Drawbacks of Data Distribution: The primary drawbacks of distributed database systems are the added complexity needed to ensure proper coordination between the sites. This increas
Name the three major set of files on disk that compose a database in Oracle. There are three main sets of files on disk that compose a database. All the files are binary. These
Write the motivations led to development of OO-DBMS? 1. Programmer frustration with RDBMSs. 2. Requirement for special features.
Question: A DBMS built for Online Transaction Processing (OLTP) is generally regarded as unsuitable for data warehousing. Each system is designed with a different set of requir
various techniques of hashing?
Consider entity type Employee with attributes empNumber (this is unique), empName, and the year when he/she was hired. An employee can either be a technical employee, a marketing e
What is substitutability? Any method of a class-say A can equally well be adjured with any object belonging to any subclasses B of A. This characteristic leads to code reuse, a
You are managing the following database system: • DBMS: Oracle 11g • OS: Sun Solaris • System architecture: Web-based application using ASP.Net • Purpose of Server: HR manage
what characterizes the levels in RAID technology
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd