Direct Query limitations
The following section describes the limitations of Direct Query.
The following limitations apply when using and creating Direct Query apps:
- Direct Query apps can only use a single database.
- Direct Query apps can only reload Direct Query data sources.
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The Qlik Analytics mobile app does not support Direct Query.
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Direct Query capabilities are dependent on the capabilities of the underlying cloud databases and SQL pushdown.
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Direct Query performance is heavily affected by the performance of the underlying data source.
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What is supported in Direct Query mode might be different in each app depending on the data connection type. Each database might treat the execution of queries differently.
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It is not possible to use Qlik Data Gateway - Direct Access data connections in Direct Query.
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Security is handled by the database.
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Direct Query app type can only be selected for databases where Direct Query mode is supported.
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To use Direct Query on a database, you need to have permission to read from the database.
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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.
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Interception and local execution of some operations will only follow the caching paradigm, which the user must turn on.
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The following activity center actions are not supported:
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Open without data
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Evaluate performance
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Reload
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Schedule reload
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Direct Query apps can be published to managed spaces, but users in the managed space must have access to the data connection used by the Direct Query app.
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There is a 1 million row limit on what can be returned in a single query to an underlying database.
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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.
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Sorting options are not supported in filter pane visualizations. Default sorting is applied automatically.
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Direct Query filter panes do not indicate excluded values in gray. For more information, see Selection states.
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Visualization extensions are not supported.
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Embedding app content is not supported.
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Sharing and downloading app content is not supported.
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Reporting capabilities, including the Qlik Reporting Service value-add features and subscription reports, are not supported in Direct Query apps.
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Context sensitive help is not available in the expression editor for Snowflake functions.
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The following field search capabilities are not supported:
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Fuzzy search
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Compound search
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Implicit word-based search or word-based search expressed with "^"
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"-" and "+" symbols indicating additional search semantics instructions
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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.
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LIMIT n will have n greater than or equal to 1000 in almost all generated SQL data queries. Specific charts have the following considerations:
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Scatter plot chart data queries have a default n of 2500.
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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.
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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.
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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.
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The row data fetch limits will also impact on-demand app-generated content from a Direct Query app.
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