Redash

Redash is an open source data visualization and collaboration platform that enables teams to connect to any data source, write queries, create visualizations, and build dashboards that can be shared across the organization. With its SQL-first approach and multi-source architecture, Redash is particularly popular with data engineers and analysts who want a lightweight, self-hosted alternative to heavy enterprise BI platforms.

The query editor in Redash is the primary workspace for data exploration. It provides a feature-rich SQL editing environment with syntax highlighting, schema browsing, query autocompletion, and query history. Queries can be executed on demand, scheduled for automatic refresh, and parametrized with user-fillable inputs that allow non-technical users to customize query results within predefined bounds. Query snippets allow commonly used SQL fragments to be saved and reused across multiple queries.

Data source connectivity is broad and flexible. Redash supports connections to PostgreSQL, MySQL, SQL Server, SQLite, MariaDB, Amazon Redshift, Google BigQuery, Snowflake, ClickHouse, Apache Hive, Apache Impala, Presto, Trino, Databricks, DynamoDB, MongoDB, Elasticsearch, InfluxDB, Prometheus, Google Analytics, and many others through its data source plugin system. REST API data sources and custom Python data sources extend connectivity to virtually any data provider.

Visualization options in Redash cover the most common chart types needed for data analysis. Available visualizations include table, line chart, bar chart, pie chart, scatter chart, area chart, heatmap, box plot, pivot table, cohort analysis, funnel chart, word cloud, map (choropleth and point), counter, and Sankey diagram. Each visualization type has configuration options for axes, colors, labels, and sorting.

Dashboards in Redash are assembled by adding visualizations from saved queries to a configurable grid layout. Dashboard widgets can be resized and repositioned, and multiple visualizations from different queries and data sources can be combined in a single dashboard. Dashboard parameters allow viewers to filter all widgets simultaneously, and embeddable dashboards can be shared with external stakeholders without requiring a Redash login.

The alerting system in Redash allows users to define threshold conditions on query results and receive notifications through email, Slack, HipChat, Mattermost, PagerDuty, webhooks, and other channels when the condition is met. Alerts are evaluated automatically after each scheduled query refresh.

User management in Redash supports groups and data source permissions that control which users can access which data sources and which queries and dashboards they can view or edit. This makes Redash suitable for organizations that need to share data access broadly while maintaining appropriate boundaries between teams and sensitive data sets.

Redash can be self-hosted using Docker Compose or deployed on cloud infrastructure, and it integrates with PostgreSQL as its own metadata store and Redis for job queuing. The active open source community maintains a large library of data source connectors and contributes features and bug fixes to the project.