You can select the query mode to use in Data Virtualization.
Choose between running queries in Max Consistency mode or in Max Pushdown, which can help you to
maximize performance.
- On the navigation menu, click to reveal the service menu.
The service menu opens to the
Data sources page by default.
- On the service menu, click .
- In the Advanced settings section, select one of the following
query modes:
- Max Pushdown mode: Ignores semantic difference between Data Virtualization and data source for single-source queries.
Therefore, more single-source queries might be fully pushed down to data source, improving query
performance. Query results are consistent with data source semantics for fully pushed down queries
in this mode. Max Pushdown impacts only single-source queries.
- Max Consistency mode: Follows Data Virtualization semantics to evaluate whether operations can
be pushed down to the data source. If the operation that is run on the data source generates the
same result as Data Virtualization, the operation can be
pushed down. Queries in this mode might be fully pushed down if the remote data source has the same
semantics as Data Virtualization.