Why use TimescaleDB over PostgreSQL?
TimescaleDB is PostgreSQL. Because TimescaleDB is a PostgreSQL extension, the question isn’t “Why use TimescaleDB over PostgreSQL?”, but rather, “Why use TimescaleDB and PostgreSQL over PostgreSQL alone?”
TimescaleDB expands PostgreSQL in 3 key areas:
Alongside these features, you still get 100% of regular PostgreSQL. That’s because TimescaleDB is an extension, not a fork. With your TimescaleDB database, you can install other PostgreSQL extensions, make full use of the type system, and benefit from the diverse PostgreSQL ecosystem.
Better performance at scale
TimescaleDB performs orders of magnitude better at high data volumes. Your applications are future-proof even if they grow rapidly.
1000 times faster performance for time-series queries
We tested the performance of TimescaleDB + PostgreSQL against PostgreSQL alone, using different time-based queries. We used one month’s worth of data, which amounted to one billion rows organized into four-hour partitions. Running 100 queries at a time, TimescaleDB + PostgreSQL consistently outperformed a standard PostgreSQL database. Queries are up to 1000 times faster.
This table shows the query latency of PostgreSQL compared to TimescaleDB + PostgreSQL. The data uses PostgreSQL 14 and TimescaleDB 2.7. For more information on the comparison, see the comparison blog post.
TimescaleDB achieves this performance by using hypertables. With hypertables, your data is automatically partitioned by time, but you get the simplified experience of interacting with a single, virtual table.
Partitioning makes queries faster by quickly excluding irrelevant data. It also allows us to make enhancements to query planning and execution.
When hypertables are compressed, performance can improve even more, because less data needs to be read from disk.
Millisecond performance for commonly run aggregate queries
When working with time-series data, you often need to aggregate data by grouping over minutes, hours, days, months, or more. TimescaleDB’s continuous aggregates make time-based aggregates faster. When comparing continuous aggregates to directly querying raw data, TimescaleDB often means queries take milliseconds, instead of minutes or hours. For more information, see the FlightAware case study.
Continuous aggregates automatically materialize aggregated data. They also stay up-to-date automatically, providing a more convenient developer experience. With automatically refreshing continuous aggregates, you can downsample your data automatically. You can delete the underlying raw data on a schedule, while the continuous aggregate stores the aggregated data.
Continuous aggregates are similar to PostgreSQL materialized views, but they solve some of their limitations. PostgreSQL materialized views recreate the entire view every time the materialization process runs, even if little or no data has changed. Materialized views also don’t provide any data retention management. Any time you delete raw data and update the materialized view, the aggregated data is removed as well.
In contrast, TimescaleDB’s continuous aggregates automatically update on the schedule you set. They refresh only the portions of new data that were modified since the last materialization. And they can have data retention policies applied separately from the raw data, so you can keep old data in a continuous aggregate even as you delete it from the underlying hypertable.
Scale PostgreSQL horizontally
With TimescaleDB multi-node, you can scale PostgreSQL horizontally to insert over 1 million rows per second into petabyte-scale datasets, while maintaining ingest and query performance.
TimescaleDB multi-node works with distributed hypertables, which automatically partition your data across multiple data nodes. This happens behind the scenes, and you still get the simplified experience of interacting with your distributed hypertable in the same way as a regular PostgreSQL table.
Lower storage costs
With compression and downsampling, TimescaleDB can dramatically reduce the size of your tables and reduce your storage costs.
Greater than 90% storage savings with best-in-class compression algorithms
TimescaleDB provides native columnar compression. Users often see their disk consumption decrease by over 90%, compared to storing the same amount of data in standard PostgreSQL. If you’re using Timescale Cloud, which decouples billing for compute and storage, enabling compression significantly decreases your storage bill.
This chart shows the size of an example dataset when stored in TimescaleDB with compression, compared to its size in a regular PostgreSQL database. For more information on the comparison, see the comparison blog post.
With compression policies, chunks can be compressed automatically once all data in the chunk has aged beyond the specified time interval. In practice, this means that a hypertable can store data as row-oriented for newer data, and column-oriented for older data.
Having the data stored as both row and column store also matches the typical query patterns of time-series applications. This improves overall query performance.
Automatic downsampling and removal of old data with one command
To save even more on storage costs, you can set up an automatic data retention policy with one SQL command. By combining continuous aggregates and data retention policies, you can downsample data and drop the raw measurements. This allows you to retain higher-level rollups of historical data. You have control over the granularity of your data and your storage costs.
To set this up in standard PostgreSQL, you’d either need to DELETE
individual records, which is inefficient, or set up declarative partitioning and automation yourself.
Features that speed up development time
TimescaleDB adds many features to standard PostgreSQL, which make it faster to build and run time-series applications. This includes a library of over 100 hyperfunctions. These hyperfunctions improve the ergonomics of writing complex SQL queries, including queries that handle count approximation, statistical aggregates, and more. TimescaleDB also includes a job-scheduling engine for setting up automated workflows.
Hyperfunctions that make data analysis easy in SQL
TimescaleDB includes a library of more than 100 hyperfunctions. These functions simplify calculations that would otherwise be complex in SQL, including time-weighted averages, downsampling, complex time-bucketing, and backfilling.
This example shows average temperature every day for each device over the last seven days, carrying forward the last value for missing readings:
SELECT
time_bucket_gapfill('1 day', time) AS day,
device_id,
avg(temperature) AS value,
locf(avg(temperature))
FROM metrics
WHERE time > now () - INTERVAL '1 week'
GROUP BY day, device_id
ORDER BY day;
To learn more, see the hyperfunctions API documentation.
Built-in job scheduler for workflow automation
TimescaleDB lets you add user-defined actions, so you can execute custom stored procedures on a schedule. You can rely on user-defined actions to calculate complex service level agreements, send event emails based on data correctness, poll tables, and more.
User-defined actions provide similar capabilities to a third-party scheduler such pg_cron
, but without the need to maintain multiple PostgreSQL extensions or databases.