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Anonymous's avatar
Anonymous
Not applicable
4 years ago
Solved

Query Folding with Databricks.Catalogs Connector

Hi all,   I'm using Databricks.Catalogs connector to get data from Databricks Database Tables in the import mode (using the online Dataflows).  The problem is that my query is not folded even thou...
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  • Anonymous's avatar
    Anonymous
    3 years ago

    I found a great solution and does not break Databricks Query Folding 

     

    use Databricks.Query instead of Databricks.Catalogs

     

    If you want to lightweight your loading process

     

    create a parameter  like date_filter

     

    let
    Source = Databricks.Query("warehouses" , [] ),
    part1 = "select * from TYPE YOUR TABLE",
    part2 = " WHERE snapshot_date > "&"'"&date_filter&"'",
    MyQuery = Source(part1 & part2)
in
    MyQuery

     

badac002's avatar
badac002
Frequent Visitor
2 years ago

Bumping this topic. Can someone point me to a guide on query folding in Power Query with the Azure Databricks connector?

 

The behavior mentioned in the above post is still present in 2024 in Power Query Online. In my opinion, it is unacceptable that simply selecting a table from Unity Catalog yields a "Will not fold" indicator. Even in Power BI Desktop, users will not see the "View Native Query" option, which would indicate the query is folding. I should not have to instruct users to use the Azure Databricks connector and then edit their M code to switch to Databricks.Query (which has no documentation other than this random LinkedIn post https://www.linkedin.com/uas/login?session_redirect=https%3A%2F%2Fwww.linkedin.com%2Fpulse%2Fquery-folding-azure-databricks-tushar-desai)

I can't be the only only one having trouble with this. I am trying to instill best practices with my community, and it is difficult when the Azure Databricks connector behaves so differently from others. Can anyone point me to a proper guide on how users can be sure their queries are folding with Databricks?

  • jakaihammuda's avatar
    jakaihammuda
    Helper III
    2 years ago

    Yep, im struggling to get it working. 

  • Stachu's avatar
    Stachu
    Community Champion
    2 years ago

    It seems that when the native query is provided in the connection UI the fold is also not breaking. PowerBI wraps the Databricks.Catalog in Value.NativeQuery, like this:

    let
    Source = Value.NativeQuery(Databricks.Catalogs(server, http, [Catalog="samples", Database=null, EnableAutomaticProxyDiscovery=null]){[Name="samples",Kind="Database"]}[Data], "select * from nyctaxi.trips", null, [EnableFolding=true])
in
    Source

    When analysed using the Diagnose feature it shows the source query is folded even though the View Native Query option is greyed out, but I must say I didn't verify it on the Databricks end