Requirements and compatibility#

Querona server operates as a Windows Service and is entirely self-hosted, therefore no additional Windows components are required, besides dependencies explicitly stated below.


Below are the recommendations for the server deployments:

  • A dedicated machine to simplify tuning, management, and diagnostics

  • Windows Active Directory

  • Multi-core server hardware with two or more cores for production deployments

The disk I/O performance of any modern server-class system should be sufficient. Memory requirements are highly dependent on the product target usage, but 8 GB of RAM may be sufficient for deployments that do not heavy utilize built-in Apache Spark. For small deployments, 4 GB of RAM is sufficient and should be considered a minimum, unless the specific deployment is tested and verified to require less memory.

Supported database management systems for caching#

Querona supports multiple database platform to cache and process materialized data:

Deployment of each of the platforms is project-specific. Please follow the recommendations and practices documented by the respective vendors.


Regarding Spark 2.1.1 - there’s a known bug that causes this version to fail during startup. Please contact us if you are using this version of Spark.

Operating systems#

  • Windows Server 2022 (Essentials, Standard, Datacenter)

  • Windows Server 2019 (Essentials, Standard, Datacenter)

  • Windows Server 2016 (Essentials, Standard, Datacenter)

  • Windows Server 2012 R2 (Essentials, Standard, Datacenter)

  • Windows 11 x64 (Professional, Enterprise)

  • Windows 10 x64 (Professional, Enterprise)

  • Windows 8.1 x64 (Professional, Enterprise)

Server core Windows Server installations are not supported.

Querona can be installed only on a 64-bit Windows Server or Client operating system.

Required platforms and components#

.Net 8 runtime#

If your system does not have the required .Net 8 version installed, please download the Hosting Bundle installer from latest DotNet Core bundle download page and install.

.Net Framework 4.7.2 runtime or later#

.Net Framework system requirements documentation is available from Microsoft.

If your system does not have the required .Net Framework version built-in, please download it from Windows Update or download the offline installer, that can be found under .Net 4.7.2 offline installer.


.Net Framework is required only by the Querona installer for Windows. The service uses .Net 8 during runtime.

Optional platforms and components#

Microsoft SQL Server Express, Standard, Enterprise 2012 or higher#

Sql Server is an optional database platform used for metadata and storage of audit log. By default we use SqLite for metadata, however, for larger deployments an enterprise-grade database server is recommended.

JRE x64 v8#

The Apache Spark runtime depends on the JRE x64 v8. If a compatible JRE is found at the time of installation (like Oracle JRE), it will be automatically used. In other cases, a build-in Zulu JRE will be installed and used as the Java runtime.

Virtualization environments#

We support the virtualization in Microsoft Hyper-V or VMWare environments. Other platforms were not tested with but every virtualizer that is certified to work with supported version of Windows should work fine.

Metadata databases#

Querona requires two databases for operations:

  • Metadata database, where we keep the metadata.

  • Apache Spark MetaStore database, where Spark keeps its metadata.

Both databases do not depend on each other and can be hosted using different technologies.

For user convenience and quick deployment in development, test or evaluation scenarios, Querona supports a built-in SQLite file database for metadata storage and Derby for Apache Spark.

The following database technologies are supported:

Metabase owner

Supported technologies


SQLite (built-in), Microsoft SQL Server 2012 or later, SQL Azure

Apache Spark

Derby (built-in), Microsoft SQL Server 2012 or later, SQL Azure

The following versions of SQL Server are supported for Querona MetaBase and Apache Spark MetaStore:

  • SQL Server 2022

  • SQL Server 2019

  • SQL Server 2016

  • SQL Server 2014

  • SQL Server 2012 (minimum SP1)

Your limits on database read operations#

We do not support any read operations against the metabases that originate from queries, scripts, .dll files, and so on, not provided with Querona or by its support teams. If Support determines that those read operations prevent them from solving your problem, the entire database will be unsupported. To return the database to a supported state, all unsupported read operations must stop.

SQL Server editions#

We support the following editions of SQL Server and SQL Azure as metadata store:

  • Express,

  • Standard,

  • Enterprise,

  • SQL Azure v11 or later.

The SQL Express edition is recommended only for evaluation purposes, personal use, or for small teams. We recommend SQL Server Standard, Enterprise or SQL Azure v11 or later for all other scenarios.

Active Directory#

You can install Querona on a single server that is joined to an Active Directory domain or that is a member of a workgroup.


Active Directory environment is not required but is fully supported and recommended for enterprise deployments.

Service account#

Querona Server requires a service account. That service account becomes the user identity of the installed Windows Service handling requests to Querona.

During installation, you have to specify a user account. The Log on as a service permission will be granted by installer automatically. You must not use the account that you use to install Querona. For example, if you are logged in as domainuser1 when you install Querona, do not use domainuser1 as the account for Querona.


Service account should not be a member of Local Administrators group on Windows. In such case, required permissions will be granted to Administrators group, not the account itself. If at a later time, such account administrators group membership is revoked, you will have to manually grant necessary permissions or reinstall Querona.

Installer grants Log on as a service permission to selected account only during installation.

You may use different accounts to install and run Querona Server:

  • NetworkService

  • LocalService

  • Dedicated local account

  • Dedicated domain account

Best practices for accounts:

  • use Network Service or a dedicated domain account, because they present network credentials, allowing Querona to transparently authenticate against data sources that support Windows Integrated Authentication

  • use accounts that have permissions to authenticate users against a domain, because it allows Querona to authenticate incoming users by Windows Integrated Authentication


It is not recommended to manually change service account after installation. Please reinstall Querona Server if you need to change the service user account.

If re-installation of Querona Server is not desired or possible, and manual change of service account after installation is absolutely necessary, you must ensure that:

  • the Log on as a service permission is granted to the new service user,

  • the read and write permissions to Apache Spark warehouse directory are granted to the new service user,

  • necessary permissions to access Querona metabase and Spark metabase deployed on SQL Server are granted to the new service user,

  • necessary permissions to access data sources are granted to the new service user,

  • necessary http.sys port reservations are available to the new service user.

Hardware recommendations#

Querona can scale from a basic installation on a laptop all the way up to a highly available deployment. The following recommendations should apply to most Querona deployments, but your requirements may vary depending on the usage of your team. For example, if you have particularly large data set that you want to materialize using built-in Apache Spark, you may need higher specification machines than what is listed below. Note that all of the machines discussed below could be either physical or virtual.

A single machine, with one dual-core processor, 8 GB of RAM, and a fast hard disk drive. Scaling server up can enable it to handle a larger number of users and workload.

For evaluation or personal use, you can use a basic configuration with as little as 4 GB of RAM, but clearly, this would not be recommended for a production server used by more than one person.

Natural Languages#

You can install Querona on supported operating systems in various languages. However, the user interface will be available in US English, German, and Polish.


You can use these browsers to access the web GUI:


Supported Version

Known issues


most recent


most recent


most recent


most recent

Internet Explorer

11 and later (not recommended)

May not render Apache Spark application portal properly. For example, query plans may not show up.

Third-Party Software#

Querona Server is provided with certain third-party software, including but not limited to open-source software, which is licensed under its applicable third-party software license agreement. For license information about third-party software distributed with Querona software, refer to your Querona license agreement and the 3rd-party-licenses.txt file.