The elapsed time of the first query that triggers regeneration of metadata can be greater than that of subsequent queries that use that metadata.
If this increase in the time of the first query is unacceptable, make sure the cache is up-to-date by running the REFRESH TABLE METADATA command.
For Superset to connect to a specific schema, there’s a schema parameter you can set in the table form.
You may want to attempt the next step (“Superset installation and initialization”) and come back to this step if you encounter an error.
Here’s how to install them: For Debian and Ubuntu, the following command will ensure that the required dependencies are installed: It is recommended to install Superset inside a virtualenv.
To enable support for long running queries that execute beyond the typical web request’s timeout (30-60 seconds), it is necessary to deploy an asynchronous backend, which consist of one or many Superset worker, which is implemented as a Celery worker, and a Celery broker for which we recommend using Redis or Rabbit MQ.
It’s also preferable to setup an async result backend as a key value store that can hold the long-running query results for a period of time.
This is provided at This file also allows you to define configuration parameters used by Flask App Builder, the web framework used by Superset.
Please consult the Flask App Builder Documentation for more information on how to configure Superset.
When you use this feature, Drill generates a metadata cache file.
Drill stores the metadata cache file in a directory you specify and its subdirectories.
Please make sure to change: Superset does not ship bundled with connectivity to databases, except for Sqlite, which is part of the Python standard library. Flask-Cache supports multiple caching backends (Redis, Memcached, Simple Cache (in-memory), or the local filesystem).
You’ll need to install the required packages for the database you want to use as your metadata database as well as the packages needed to connect to the databases you want to access through Superset. If you are going to use Memcached please use the pylibmc client library as python-memcached does not handle storing binary data correctly. For setting your timeouts, this is done in the Superset metadata and goes up the “timeout searchpath”, from your slice configuration, to your data source’s configuration, to your database’s and ultimately falls back into your global default defined in Postgres and Redshift, as well as other database, use the concept of schema as a logical entity on top of the database.
If you remove a package from the cache, you do not affect the copy of the software installed on your system.