7.8 KiB
| name | description |
|---|---|
| timescaledb | Manage time-series data in PostgreSQL with TimescaleDB. Use this skill to install, configure, optimize, and interact with TimescaleDB for high-performance time-series data storage and analysis. This includes creating hypertables, continuous aggregates, handling data retention, and querying time-series data efficiently. |
TimescaleDB Skill
Manage time-series data in PostgreSQL using TimescaleDB, extending PostgreSQL for high-performance time-series workloads.
When to Use This Skill
Use this skill when you need to:
- Work with time-series data in PostgreSQL
- Install and configure TimescaleDB
- Create and manage hypertables
- Optimize performance for time-series data
- Implement continuous aggregates for rollup data
- Manage data retention and compression
- Query and analyze time-series data
- Migrate existing PostgreSQL tables to hypertables
- Integrate with other PostgreSQL tools and extensions
Not For / Boundaries
This skill is NOT for:
- General PostgreSQL administration (use a specific PostgreSQL skill for that)
- Deep database tuning unrelated to time-series performance
- Replacing dedicated time-series databases if TimescaleDB's PostgreSQL foundation is not a requirement
- Providing data visualization beyond basic SQL queries (use a BI tool or separate visualization library)
Quick Reference
Installation & Configuration
Install TimescaleDB Extension (Debian/Ubuntu):
sudo apt install -y postgresql-{{pg_version}}-timescaledb
sudo pg_createcluster {{pg_version}} main --start
sudo pg_ctlcluster {{pg_version}} main start
sudo -u postgres psql -c "CREATE EXTENSION IF NOT EXISTS timescaledb CASCADE;"
(Replace {{pg_version}} with your PostgreSQL version, e.g., 16)
Configuration (postgresql.conf):
# Add to postgresql.conf
shared_preload_libraries = 'timescaledb'
timescaledb.max_background_workers = 8 # Adjust based on CPU cores
max_connections = 100 # Adjust based on workload
(After changes, restart PostgreSQL: sudo systemctl restart postgresql)
Hypertables
Create Hypertables:
CREATE TABLE sensor_data (
time TIMESTAMPTZ NOT NULL,
device_id INT,
temperature DOUBLE PRECISION,
humidity DOUBLE PRECISION
);
SELECT create_hypertable('sensor_data', 'time');
Convert Existing Table to Hypertable:
SELECT create_hypertable('your_existing_table', 'time_column', migrate_data => true);
Show Hypertables:
\d+
SELECT * FROM timescaledb_information.hypertables;
Continuous Aggregates
Create Continuous Aggregate:
CREATE MATERIALIZED VIEW device_hourly_summary
WITH (timescaledb.continuous) AS
SELECT
time_bucket('1 hour', time) AS bucket,
device_id,
AVG(temperature) AS avg_temp,
MAX(temperature) AS max_temp
FROM sensor_data
GROUP BY time_bucket('1 hour', time), device_id
WITH NO DATA; -- Initially create without data
-- Refresh the continuous aggregate
CALL refresh_continuous_aggregate('device_hourly_summary', NULL, NULL);
Get Continuous Aggregates Info:
SELECT * FROM timescaledb_information.continuous_aggregates;
Data Retention & Compression
Set Data Retention Policy (Drop data older than 3 months):
SELECT add_retention_policy('sensor_data', INTERVAL '3 months');
Enable Compression (Compress data older than 7 days):
ALTER TABLE sensor_data SET (timescaledb.compress = TRUE);
SELECT add_compression_policy('sensor_data', INTERVAL '7 days');
Show Compression Status:
SELECT * FROM timescaledb_information.compression_settings;
Querying Time-Series Data
Basic Time-Range Query:
SELECT * FROM sensor_data
WHERE time >= NOW() - INTERVAL '1 day'
AND time < NOW()
ORDER BY time DESC;
Gapfilling and Interpolation:
SELECT
time_bucket('1 hour', time) AS bucket,
AVG(temperature) AS avg_temp,
locf(AVG(temperature)) OVER (ORDER BY time_bucket('1 hour', time)) AS avg_temp_locf
FROM sensor_data
GROUP BY bucket
ORDER BY bucket;
High-Performance Queries
Approximate Count:
SELECT COUNT(*) FROM sensor_data TABLESAMPLE BERNOULLI (1);
Top-N Queries:
SELECT time, device_id, temperature
FROM sensor_data
WHERE time >= NOW() - INTERVAL '1 day'
ORDER BY temperature DESC
LIMIT 10;
Examples
Example 1: IoT Sensor Data Pipeline
- Input: Stream of sensor readings (time, device_id, value)
- Steps:
- Create a hypertable for
iot_readings. - Ingest data into the hypertable.
- Create a continuous aggregate to compute hourly average readings.
- Query the continuous aggregate for a specific device's hourly trend.
- Set a retention policy to keep only 1 year of raw data.
- Create a hypertable for
- Expected output / acceptance: Efficient storage, automatic hourly rollups, and proper data pruning.
Example 2: Financial Tick Data Analysis
- Input: High-frequency financial tick data (timestamp, symbol, price, volume)
- Steps:
- Create a hypertable
tick_datawith proper chunk sizing for high ingest rate. - Enable compression for older
tick_data. - Query
tick_datato calculate 5-minute VWAP (Volume Weighted Average Price) for a specific symbol. - Visualize the VWAP over the last trading day.
- Create a hypertable
- Expected output / acceptance: Ability to ingest and analyze millions of rows/second, with optimized storage and fast analytical queries.
Example 3: Monitoring System Metrics
- Input: Server metrics (timestamp, host_id, cpu_usage, memory_usage, network_io)
- Steps:
- Create a hypertable
system_metricspartitioned bytimeandhost_id. - Use a
time_bucket_gapfillquery to find CPU usage for all hosts over the last 24 hours, filling in missing data points. - Create an alert based on
MAX(cpu_usage)exceeding a threshold using a continuous aggregate.
- Create a hypertable
- Expected output / acceptance: Comprehensive monitoring with gap-filled data for visualization and real-time alerting.
References
references/installation.md: Detailed installation and setupreferences/hypertables.md: Deep dive into hypertable managementreferences/continuous_aggregates.md: Advanced continuous aggregate techniquesreferences/compression.md: Comprehensive guide to data compressionreferences/api.md: TimescaleDB SQL functions and commands referencereferences/performance.md: Performance tuning and best practicesreferences/getting_started.md: Official TimescaleDB Getting Started Guidereferences/llms.md: Using TimescaleDB with LLMs (e.g., storing embeddings, RAG)references/llms-full.md: Full LLM integration scenariosreferences/tutorials.md: Official TimescaleDB Tutorials and Use Casesreferences/time_buckets.md: Guide totime_bucketand gapfilling functionsreferences/hyperfunctions.md: Advanced analytical functions for time-series
Maintenance
- Sources: Official TimescaleDB Documentation, GitHub repository, blog posts.
- Last updated: 2025-12-17
- Known limits: This skill focuses on core TimescaleDB features. Advanced PostgreSQL features (e.g., PostGIS, JSONB) are covered by other specialized skills.
Troubleshooting
Slow Queries
- Ensure indexes are on
timeand other frequently queried columns. - Verify chunk sizing is appropriate for your data ingestion rate.
- Use
EXPLAIN ANALYZEto identify bottlenecks. - Consider creating continuous aggregates for frequently accessed aggregated data.
High Disk Usage
- Implement data retention policies for older, less critical data.
- Enable compression for older chunks.
- Regularly run
VACUUM ANALYZEon your tables.
Failed to Create Hypertable
- Ensure the
timecolumn isTIMESTAMPTZor a supported integer type. - The table must be empty or you must use
migrate_data => true. - Check for existing triggers or foreign keys that might conflict.
This skill provides a robust foundation for managing time-series data with TimescaleDB!