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DAX – Query Plan

June 10, 2012 Leave a comment

DAX query plan is one of the main interesting concepts in SQL 2012. Profiler gives more flexibility to understand the query, logical plan, physical plan, performance, no of cells reading i.e. rows and columns in tabular model.
Basically DAX query processing has 4 steps of  Query Begin, Logical Plan, Physical Plan and Query End
Step 1: selection of query plan at profiler as
Profiler –> Show all events –> Event Selection –> Query Processing –> DAX Query Plan


Step 2: On execution of DAX query, we can see the profiler results starts with Query Begin event as

Step 3: Here we can see the Logical plan of DAX query with different options of Vertipaq engine processing methods

Step 4: Physical plan has constructed by the engine and this is the query to fetch the results from the database

Step 5: Query processing ends with the query executed by the user

Points to consider:
1. This is only the basic information related to DAX profiler options in SQL 2012
2. DAX query plan gives more information on writing better DAX queries
3. Planning to extend this topic with practical example to improve the performance by rewriting the query using profiler information

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