Demystifying “DirectQuery” and “Connect Live”

The terms “DirectQuery” and “Connect Live” are somehow confusing. I saw lots of people are using both terminologies as alternatives. But, the context of “DirectQuery” and “Connect Live” are very different indeed. Therefore, if use a a terminology when we’re talking about a different context then the whole situation might get quite confusing. in this post I try to explain the differences and make it more clear to prevent using a wrong terminology and make sure everyone is on the same page when we’re referring to “DirectQuery” or “Connect Live”.

When we use the “DirectQuery” terminology we are actually talking about connecting from Power BI Desktop instance to an RDBMS type of data source like SQL Server DB or Oracle DB.

There are two types of data connections when we’re connecting to RDBMS like SQL Server or Oracle DB from Power BI Desktop:

  • Import Data: which literally loads data into the underlying model to make it available in memory
  • DirectQuery: which doesn’t load data into model. Instead, it runs multiple concurrent queries on the RDBMS side (data source side) and gets the results. This is good to support real-time data processing.

Note: The same principal applies to SSAS Tabular.

DirectQuery/Data Import Mode in Power BI Desktop

On the other hand, when talk about “Connect Live”, we are referring to the data connection type from a reporting tool like Power BI Desktop OR Excel to an instance of SSAS, either SSAS Multidimensional or SSAS Tabular.

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