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Helper I
Helper I

How to optimize my dax query?

Hi everyone 

I have the following dax:

I want to subtract customer f2g2h2i2  store credit balance from customer a1b1c1e1




Measure =

    SELECTEDVALUE ( 'sales'[account_credit] ),
    'sales'[customerId] = "a1b1c1e1",
    'sales'[credit_type] = "store"
        SELECTEDVALUE ( 'sales'[account_credit] ),
        'sales'[customerId] = "f2g2h2i2",
        'sales'[credit_type] = "store"
    ) + 0




When I try this I get the following error:
The resultset of a query to external data source has exceeded the maximum allowed size of '1000000' rows.


How can I optimize this so that it does not need to scan everything?




Community Support
Community Support

Hi @Forecaster 


See if this link helps: The resultset of a query to external data source has exceeded the maximum allowed size of ‘1000000’


And is the 'sales' table in DirectQuery mode? For DirectQuery, there's a one-million-row limit for cloud sources, with on-premises sources limited to a defined payload of about 4 MB per row (depending on proprietary compression algorithm) or 16MB data size for the entire visual. When a generated query retrieves an excessively large number of rows from the back-end data source, the error "The resultset of a query to external data source has exceeded the maximum allowed size of '1000000' rows." occurs. This situation can occur with a simple chart that includes a very high cardinality column, with the aggregation option set to Don’t Summarize. The visual needs to only have columns with a cardinality below 1 million, or it must apply the appropriate filters.


This article may help: Power BI — How to fit 200 million rows in less than 1GB! | by Nikola Ilic | Apr, 2021 | Towards Data...


Community Support Team _ Jing

Resolver III
Resolver III

Hi @Forecaster 

1) Is it a calculated column or a measure?
2) How many rows and column has the table Sales?
3) Do you have an example of the visual you are trying to make?

1.) It is a measure

2.) >50,000,000 rows, 25 colums

3.) the visual is just a card that shows the value returned


You can try removing columns with High cardinality (Number of distinct values). This will reduce the size of the model, thus improving the performance of any scans on the table.

Community Champion
Community Champion

Hi @Forecaster 

You can use filters in your calculations, like filter dates.


Amine Jerbi

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Hey, can you give an example? Thanks

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