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

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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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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!

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