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Write a short note on QBE?
Stands for "Query By Example." QBE is a feature involved along with various database applications which gives user-friendly techniques of running database queries. Typically without QBE, a user must write input commands using right SQL (Structured Query Language) syntax. This is a standard language in which nearly all database programs support. Therefore, if the syntax is slightly incorrect the query might return the wrong results or may not run at all. The Query By Example feature gives a simple interface for a user to enter queries. Instead of writing an whole SQL command, the user can just fill in blanks or select items to describe the query she needs to perform. For instance, a user may need to select an entry from a table called "Table1" with an ID of 123. Using SQL, the user would required to input the command, "SELECT * FROM Table1 WHERE ID = 123". The QBE interface might permit the user to just click on Table1, type in "123" in the ID field and click "Search." QBE is offered along with most database programs, by the interface is often different among applications. For example, Microsoft Access has a QBE interface known as "Query Design View" which is totally graphical. The phpMyAdmin application used along with MySQL, offers a Web-based interface whereas users can choose a query operator and fill in blanks with search terms. Whatever QBE implementation is given with a program, the purpose is the similar - to make it easier to run database queries and to prevent the frustrations of SQL errors
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