SSAS - tabular | Calculated columns exercise | Using COUNTROWS and RELATEDTABLE in calculated columns

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You can learn how to do this exercise if you attend the course listed below!

Software ==> SSAS - tabular  (30 exercises)
Version ==> SSAS 2012 and later
Topic ==> Calculated columns  (4 exercises)
Level ==> Average difficulty
Course ==> SSAS - Tabular Model
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  1. Go into SQL Server Management Studio;
  2. Open the SQL file you've just unzipped (you can press CTRL + O to do this); then
  3. Execute this script.

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Create a new project called Counting, importing the tables tblRegion, tblTown and tblCentre.  Create a calculated column in the region table to show how many rows there are in the centre table for each region:

Counting centres

The calculated column gives the same answer for every row.

 

The reason the answer is the same for every region is that no account is being taken of the relationship between the tables.  To solve this, use the RELATEDTABLE function to get:

Counting better

The RELATEDTABLE function returns the number of centres for each region which match up.

Create another calculated column giving the number of towns for each region:

Number of towns

The South-East has the most towns, it seems.

That's it!

You can unzip this file to see the answers to this exercise, although please remember this is for your personal use only.
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