Direct Query limitations

The following section describes the limitations of Direct Query.

The following limitations apply when using and creating Direct Query applications:

• Direct Query applications can only use a single database.
• Direct Query applications can only reload Direct Query data sources.

• The Qlik Analytics mobile application does not support Direct Query.

• Direct Query capabilities are dependent on the capabilities of the underlying cloud databases and SQL pushdown.

• Direct Query performance is heavily affected by the performance of the underlying data source.

• What is supported in Direct Query mode might be different in each application depending on the data connection type. Each database might treat the execution of queries differently.

• It is not possible to use Qlik Data Gateway - Direct Access data connections in Direct Query.

• Security is handled by the database.

• Direct Query application type can only be selected for databases where Direct Query mode is supported.

• To use Direct Query on a database, you need to have permission to read from the database.

• To use Direct Query on a data connection, you need to have the Can consume data permission in the space where the data connection resides.

• Interception and local execution of some operations will only follow the caching paradigm, which the user must turn on.

• The following activity center actions are not supported:

  • Impact analysis

  • Open without data

  • Evaluate performance

  • Reload

  • Schedule reload

• Direct Query applications can be published to managed spaces, but users in the managed space must have access to the data connection used by the Direct Query application.

• There is a 1 million row limit on what can be returned in a single query to an underlying database.

• The green, white and grey associative model is not supported. Because of the limitations of SQL query-based modelling, data is filtered rather than selected. For more information, see The associative selection model.

• Sorting options are not supported in filter pane visualizations. Default sorting is applied automatically.

• Direct Query filter panes do not indicate excluded values in gray. For more information, see Selection states.

• Visualization extensions are not supported.

• Embedding application content is not supported.

• Sharing and downloading application content is not supported.

• Reporting capabilities, including the Qlik Reporting Service value-add features and subscription reports, are not supported in Direct Query applications.

• Context sensitive help is not available in the expression editor for Snowflake functions.

• The following field search capabilities are not supported:

  • Fuzzy search

  • Compound search

  • Implicit word-based search or word-based search expressed with "^"

  • "-" and "+" symbols indicating additional search semantics instructions

• When a Qlik Cloud Direct Query SQL query is constructed to request row data to populate a chart, the maximum result size will be constrained by a LIMIT n (or its database-specific equivalent) included in the relevant SQL query sent to the remote database.

  This LIMIT n serves to reduce potential query performance impact and Analytics engine memory use impact by limiting the maximum number of data result rows returned for a single query result.

  • LIMIT n will have n greater than or equal to 1000 in almost all generated SQL data queries. Specific charts have the following considerations:

    • Scatter plot chart data queries have a default n of 2500.

    • For a table chart the LIMIT n can be configured explicitly up to a maximum n of 100000 using the DirectQueryRowFetchMaxCount script variable described in Direct Query script variables.

    • If DirectQueryRowFetchMaxCount is configured to be > 0 and < 2500 then the DirectQueryRowFetchMaxCountvalue will also be used to restrict the LIMIT n used to query data for a scatter plot.

  • It is important to note that the applied LIMIT discussed above applies only to data fetch queries to populate what is visible on a chart. Aggregation queries are not limited in any way and will always reflect the correct database-specific aggregation result of the complete dataset in the remote database.

  • The row data fetch limits will also impact on-demand application-generated content from a Direct Query application.

• The write table is not available in Direct Query applications.

Bookmark limitations

You can create, update, and apply bookmarks in Direct Query applications in the same way as in in-memory applications. The following limitations apply:

• Bookmark details list only the selected fields. Selected values are not shown, and value counts are shown as 0.

• When you apply a bookmark, the saved selections are applied to the current data. If the data has changed since the bookmark was created, the result can be different.

• If a field, value, or alternate state saved in the bookmark no longer exists, it is skipped without a warning. The rest of the bookmark is applied.

• Selections are cleared when a session reconnects, or when the application is refreshed after a reload. To restore the selections, apply the bookmark again.

• The set analysis expression of a bookmark is empty when it is read through the API.

For more information, see Creating bookmarks.