Today we are going to see about Data Warehouse. So, in order to do that we will go through definition of data warehouse first. Data warehouse is defined as Subject-oriented, integrated, time variant and non-volatile Collection of data In order to provide business insights And aid in the decision making process.
This is the technical definition of data warehouse Now, the terms subject-oriented, integrated, time-variant and non-volatile are the features of data warehouse Now, let’s go through the concepts of data warehouse So, Data warehouse is a relational database which is hosted on a cloud or an enterprise mainframe server Data warehouse. Takes data from various heterogeneous sources and the data can be anything, like production data, internal data, achieved data, etc.
Now it takes the data and helps in the process of analysis and decision making for any business Now, data warehouse stores large amount of data and it stores in a historical format that is more than one version of the data can be stored unlike the operational databases where each data each version will require it’s own unique identity Data warehouses can perform read and retrieve operations only Data warehouses are not programmed for write and update operations because they store data in historical format, once the data is entered into the data warehouse, it cannot be deleted either we can dump another version of the same data which can also be called as an improvement.
So, we can only read and retrieve the data in order to perform analysis and decision making process Let’s take an example of a company stores information pertaining to its employees, salaries, developed products, customer information, sales and invoices Now, the higher authority like Manager or CEO they might want to ask the question pertaining to the latest cost reduction measures or the development in the products which are ongoing or customer engagement information and how the sales are working or how are they improving or what are the benchmarks of their products so, to answer these questions you will need data warehouse.
Now, to answer these questions data warehouses can be used very efficiently they can help the employees or the higher authorities to get answers to all of these questions in a very efficient way because of the feature of the data warehouse to store the data in historical format so, they can get information, compare the data of the last year or last 12 months.
Data can be compared with previous years data In order to gain insights and work in those directions So, this is the main service of data warehouse allowing the executives to reach business decisions based on all these disparate raw data items.