Let us take a look at brief descriptions of frequent terms used in MDX query. Then after we need to select Measure from appropriate Measure Group and use related dimensions. It is important to identify Cube Name before we start writing our query. Take a look at the image given below which represents terminologies discussed above. To learn about Data Warehouse quickly refer to the article Create First Data Warehouse. Measure Group holds collection of related Measures. Measure usually contains numeric data, which can be aggregated against usage of associated dimensions. Measures are used to analyze performance of the Business. Metrics value stored in your Fact Tables is called Measure. Related member attributes using which we can study data stored in OLAP Cube Quickly and effectively. Dimensions in general we can say are the Master entities with Dimension tables contain textual descriptions about the subjects of the business. The primary functions of dimensions are to provide Filtering, Grouping and Labeling on your data.
You can take further idea on OLAP cube creation using this article Create First OLAP Cube in SSAS. OLAP Cube is the basic unit of storage for Multidimensional data, on which we can do analysis on stored data and study the various patterns. Initially, I found it very confusing to understand all these when I was new, but I don't want you to be stuck on this all, so let us begin. We need to have a clear idea in our mind about the various concepts and terminologies used while working with MDX Query. Introduction to Basic Concepts Used within MDX Query What do you mean by dimensions in Query? In general, we can say entities with related member details using which you have planned to study & analyze Data in OLAP Cube. MDX is also used to write expressions for custom calculation in Power Pivot and for creation of Calculated member in OLAP Cube. While MDX Can process more dimensions in Query. SQL Query designed to handle only two dimension while processing tabular data. Key difference between MDX and T-SQL is MDX Query build Multidimensional View of the data, where T-SQL builds Relational View. MDX Query Language is used to retrieve information stored in OLAP Cube created in various technologies like Microsoft SQL Server Analysis Services(SSAS), Oracle, Tera data, etc. So I have taken this small step to write an article and share with you all, so you can Learn Custom MDX with ease and enjoy.
While we Google, we can find some good articles on this topic, but I did not find an article with all stuff which I am looking for in one when I was searching as a beginner in this direction. In this article, we will go through some basic concepts and terminologies used while writing MDX Queries on your OLAP Cube, We will also look into Why-What and How of MDX Query.