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Anonymous
Not applicable

left join two tables both generated from DAX

Hi All, i have a seemingly extremely simple left join to create a combined table in Power BI desktop

 

I have table 1 which all combinations of 'Month' and 'Customers' (e.g.  all months by all customers), table 2 with same columns but only with months or customers that have had transactions and the 'transaction amount' as third column, i want to do a left join so that i end up all customers and all months, so that some custoemrs would then have lots of blank 'transaction amount' for the months where they haven't had any transaction.

 

Both tables have been created with DAX. 

 

I tried NATRUALOUTERLEFT, all variations of SELECTCOLUMNS but to no avail.  Any help would be much appreciated!

2 REPLIES 2
Anonymous
Not applicable

this is great! so simple and clear.  Thanks

johnt75
Super User
Super User

You could add a column to table 1 like

Transaction amount =
LOOKUPVALUE (
    'Table 2'[Transaction amount],
    'Table 2'[Month], 'Table 1'[Month],
    'Table 2'[Customer], 'Table 1'[Customer]
)

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