Implementation of Query-by-Example : a nonprogrammer's data retrieval language

One of the main requirements for a database system to be successful is that naive users who know little about programming should be able to learn and use the database system easily. Many query languages have been designed to meet this requirement. It appears that the Query-by-Example database manipulation language is easier to learn and easier to use than most data manipulation languages. The operation of Query-by-Example is similar to the manual table manipulation, and captures the simplicity, symmetry, and neutrality of the relational model. The query is expressed by filling in the appropriate table spaces on the screen of a video terminal with an example of the solution. The basic concepts of the Query-by-Example language and its implementation on the VAX-11 computer running under VMS are discussed.