Every organization deals with vast amounts of data which is stored in different formats or patterns developed on different platforms by different developers and further form different database structures. This brings hurdles on the path of analysts or users with respect to its access. Thus, organizations have to write and maintain perhaps hundreds of programs that extract, prepare, and consolidate data for its use. All this process is done with respect to Data Warehouse.
Thus ,we can define a data warehouse as “A data warehouse is a subject oriented, integrated, non-volatile and time-variant collection of data in support of management’s decision.”
Building of efficient Data Warehouse and its maintenance involves extraction, cleaning and filtering of data etc. It is a costly and time consuming process, as this is performed before requirements are gathere-d. To overcome this problem, we should use such a technique that helps in exploring and clarifying each requirement in detail which can be considered while constructing the Data Warehouse at an early phase.
Data Warehouse must be designed keeping in mind the requirements for decision making which is often derived from the data sources.
While working towards the solution i.e. Building an efficient Data Warehouse we have a number of techniques available. The technique ‘Requirement Analysis’ of ‘Requirement Engineering’ can be combined with the Requirement gathering techniques of Data Warehouse i.e. ‘Interview’ and ‘Survey Method’ in order to build an effective data warehouse.
The “Interview Technique” can be regarded as one of the best suitable technique for solving this problem. Key facts that should be considered while applying this technique is that the questions used in the interview should not reflect the interviewer’s preconceived ideas, as it can influence the responses. During the Interview, closed questions should not be asked and stressed upon because it limits the input with respect to the subject.