Data Warehousing is a method that is generally used to collect and handle data from various other sources to provide the business a meaningful business insight. A data warehouse is specifically created for the goals of support management decisions. The Data Warehouse has two main parts which are as follows −
Physical store − A Microsoft SQL Server database that it can query using SQL queries, and an OLAP database that it can need to run reports.
Logical schema − A conceptual model that maps to the data in the physical store.
The physical store for the Data Warehouse contains one database that it can query using SQL queries. The physical store includes all the data that it has imported from multiple sources. Commerce Server automatically constructs the physical store for the Data Warehouse in both the SQL Server database and the OLAP database.
The Data Warehouse supports the data necessary for some Commerce Server documents available in the Analysis modules in Business Desk. There is no requirement for us to directly change the physical store for the Data Warehouse. If it is required to extend the Data Warehouse, for instance, to encompass third-party data, a site developer can programmatically insert the fields it can need through the logical schema.
The logical schema supports a logical view of the data in the Data Warehouse and provides an effective import process. For instance, a site developer needs the logical schema to change the location of data stored in the basic physical tables.
When a site developer writes a program to insert, update, or delete data in the Data Warehouse, the developer connects with the logical schema. When Commerce Server connects data in the Data Warehouse, it connects the data through the logical schema. Only the site developer required accurate knowledge of the logical schema.
A logical schema contains the following which is as follows −
Class − A logical set of data members. For instance, the RegisteredUser class includes data members defining a registered user.
Data member − A structure that saves an element of data. For instance, the E-mail data member of the RegisteredUser class stores the e-mail address for a registered user.
Relation − A connection among two classes in a parent-child relationship. This relationship describes the number of instances of each class, and it supports the mechanism for sending data members between classes.
For example, RegisteredUser is a parent to the child class Request. There can be some requests for one registered user. The logical schema uses classes, data members, relations, and several data structures to map records in the physical store.