Data warehousing is a niche field that requires specialist knowledge about data storage, data analysis and data mining. According to the father of data warehousing, Bill Inmon, “data warehouse is a subject oriented, integrated, non-volatile and time variant collection of data in support of the management’s decisions”.
In simple words, it is a repository of data which is created by collating data from more than one source. This data is used as information to while preparing trend reports used often for quarterly or annual comparisons. Most of database administrators confuse data warehouse experts initially start with database administration and later move on to specific tools in data warehousing. There are a host of differences between the traditional operational database and data warehouse. An operational database is application oriented, deals with multiple diverse sources, can be updated and available in real time. A career in data warehousing requires a solid understanding of modeling philosophies and warehouse development lifecycle.
If you are transitioning from an operational Database administrator to Data warehouse administration first you should be clear about the direction that you intend to take your career forward. A data warehouse is essentially built on business functions unlike operational database which is built on information requirements. As a database administrator you should be able to figure out which features will be supported by your enterprise database in a data warehousing environment. Newer databases come integrated with features that directly address concerns related to a data warehouse. Oracle is the enterprise database mostly used in bigger firms and hence a comprehensive knowledge of Oracle database and its features is vital to a career in data warehousing.
Talking about the job volume in data warehousing, the field has almost a never ending requirement of new data warehouse specialists who have hands-on experience with particular vendor products. The recommended approach to pursuing a career in this field is to first acquire experience on a specific data warehousing product while working as a simple operational database administrator, as it is easier to start as DBA then Data warehousing professional. Your job in data warehousing will find many takers once you have relevant product experience on your resume. As organizations grow their data volumes, issues with storage if gargantuan amounts of data are bound to happen ad that’s when these companies start focussing on optimizing data warehouses (another name for data repository) for maximum performance. Furthermore, as discussed above, data warehousing concentrates on storage of historical data and analysing sections for improving the KPIs. With the market becoming more competitive every organization has its focus on making processes more productive and increase profit margins. Thus, data warehousing jobs have a huge role to play here.
Data warehousing has two aspects to it, namely ETL and BI. Extract-Transform-Load is a process that involves extracting data from outside sources, transforming it to suit for operations and finally loading it into the end target. BI stands for Business Intelligence. While going further into the specifications of these two processes is further from the scope of this article, it is advised to choose from these two approaches of data warehousing and find a tool that has an industry-wide acceptance. Finally, in the current scenario, your data warehousing job will pay you in gold, only if you give it the efforts it requires.