Fine Tuning Data Access

The following are properties that allow for more granular control over data access:

• QueryMode: Controls the query language used for SQL translation. Set to MDX (default) for multidimensional models or DAX for tabular models. DAX mode provides simpler data type mapping, more natural aggregation support, and efficient semantic JOINs through SUMMARIZECOLUMNS.
• QueryPassthrough: Indicates if raw queries (MDX or DAX) are being submitted. By default this is false, which causes the driver to accept only SQL-92 compliant queries.

  Setting this property to true will cause all queries to be passed through directly to Microsoft Power BI XMLA. This works with both MDX and DAX queries depending on the QueryMode setting.

• ExtraProperties: Additional properties to submit along with an MDX query.
• IncludeJoinColumns: Boolean indicating if extra columns used to make ON conditions with joins should be added.

  These do not come back with any values - they are added purely to enable tools that require them in order to automatically set up relationships between tables when creating joins.

  Note: This property is only applicable in MDX mode. DAX mode tables already use their native column relationships.

• ResponseRowLimit: Sets a calculated limit on the number of rows to allow the user to select before returning an error.

  In MDX mode, selecting only a few columns may exponentially multiply the number of expected results because of hierarchy cross-joins.

  For this reason, ResponseRowLimit is available to try and give some guidance on what types of queries are likely to result in a Timeout. May be disabled by setting to 0.

  Note: In DAX mode, queries do not suffer from the same cross-join multiplication, so row count growth is more predictable.