QL charts in DataLens On-premises. Overview

To create such charts, one uses direct queries to the source. The query is run using the source database's SQL dialect, which helps expand visualization capabilities by using database-specific transactions.

Running a query does not create a separate dataset object: a chart is generated on the fly and displayed in the preview panel.

Unlike dataset-based charts, the logic of a visualization area in QL charts favors queries against the source, i.e., the visualization area only displays the data from the query. You can also save QL charts and add them to dashboards as widgets.

Alert

When using QL charts, configure access restrictions on the data source side.

QL charts:

  • Reduce database workload by using direct queries.
  • Are only suitable for SELECT queries.
  • Enable the use of JOIN, GROUP BY, and SORT BY queries and aggregation functions in SQL queries.
  • Enable the parameterization of any part of a SQL query.
  • Support a limited set of visualizations types.

To create a QL chart, follow this guide.

Useful links

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