Best Practices for Postgres Data Management

Written by Juan José Gouvêa

Data management encompasses a broad spectrum of disciplines aimed at ensuring the accuracy, security, and accessibility of data within an organization. Managing data effectively across the data lifecycle—from its ingestion to its eventual deletion—is paramount for maintaining a stable and efficient data system—and PostgreSQL is no exception.

If you're a PostgreSQL user, implementing robust data management practices is essential for optimizing database performance, ensuring data security, and supporting decision-making processes.

In this article, we delve into the critical best practices for managing data within a PostgreSQL environment, offering insights into general data management strategies, the data lifecycle, and specialized time-series management with Timescale.

Let's start with data management strategies.

Data Management Pillars

A robust data management strategy is built upon four central pillars:

• Usability

• Security

• Documentation

• Automation

These pillars form the backbone of managing data within PostgreSQL databases. TimescaleDB supercharges PostgreSQL for time-series data and other demanding workloads, and lives at the core of our cloud service, Timescale. A fully managed cloud database can help relieve the load of data management (more on that later), allowing you to focus on development, but if you're just getting started, understanding and implementing practices around these pillars ensures a stable, efficient, and secure database environment.

Usability

Usability in data management focuses on ensuring that data is accessible and meaningful to its intended users. This involves designing database schemas that are logical and intuitive, optimizing query performance for faster data retrieval, and providing tools and interfaces that enable users to interact with the data effectively. For PostgreSQL, this could mean leveraging views, materialized views, and indexes to improve the ease of data access and analysis.

Planning for usability from the start

• Coordinating with the business plan: Your database design should align with your organization's business goals and data needs. This means optimizing the database for specific use cases rather than aiming for a one-size-fits-all solution. For instance, a database optimized for real-time analytics will differ significantly in design from one optimized for transaction processing.

• Clear naming conventions: Adopting clear and consistent naming conventions for tables, columns, indexes, and other database objects is crucial. This improves the readability and maintainability of the database. Establishing a documented style guide for naming ensures that everyone involved in the database's lifecycle can easily understand and follow the conventions.

Establishing metadata

• Using a data catalog: Implementing a data catalog helps manage metadata, making it easier for users to find, understand, and trust the data they need. A data catalog provides a centralized repository for metadata, including descriptions of data sources, datasets, and their usage.

• Follow legal standards: Ensuring that your database adheres to relevant legal standards and regulations, such as GDPR for personal data, is crucial. This involves properly classifying and handling data according to its sensitivity and the legal requirements governing it—a common requirement for many use cases.

Interoperability

• Ensure you can successfully import data from the sources you need to support: Your PostgreSQL database should be capable of efficiently importing data from various sources that your organization uses. This may involve using tools like foreign data wrappers (FDWs) for PostgreSQL, which allow you to query data from other databases or sources as if they were local tables.

Security

Security stands at the forefront of establishing and maintaining user trust and organizational reputation. Due to its intricacies, a comprehensive security strategy when managing data involves multiple layers, including data governance systems, server security protocols, and robust backup and recovery plans.

Using insights on ​data governance​ and strategic steps for developing a data ​governance strategy​, let's explore how these components contribute to a secure data environment.

Data governance system

A data governance system is essential for managing access according to metadata, ensuring that data is used and accessed in accordance with organizational policies and compliance requirements. It involves a broad coalition of roles, from business executives to IT staff and end users, all coordinated under a data governance framework.

This framework outlines policies, roles, and responsibilities to maintain data availability, integrity, usability, and security​. Utilizing data governance software can automate aspects of managing a governance program, supporting workflow management, policy development, and compliance monitoring​​.

Server security protocol

Server security protocols are critical for safeguarding data against unauthorized access and cyber threats. This includes enforcing credential security standards, conducting team training on data security practices, and leveraging cloud storage solutions known for their robust security measures​​.

Implementing least privileged access and auditing data access, especially for sensitive information like personally identifiable information (PII), further strengthens security. Cloud data security, for instance, involves encryption, access controls, and secure data storage practices that protect against data breaches and leaks​.

Backup and recovery

A strong backup and recovery system not only involves creating reliable data backups but also establishing a recovery system using database replicas to ensure business continuity in the event of data loss or system failures​​. The choice of data replication tools and disaster recovery strategies should align with your organization's specific needs and operational demands, enabling quick recovery with minimal data loss​.

In PostgreSQL, security practices include implementing role-based access control (RBAC), using strong encryption for data at rest and in transit, and regularly applying patches and updates to the database system. Additionally, understanding and utilizing PostgreSQL's built-in security features, such as row-level security and security definer functions, can further enhance the security of your data.

Documentation

As every developer knows, documentation is a cornerstone of any robust data management system, acting as the bedrock for sustainability and scalability. It provides a clear roadmap of the database architecture, data models, processes, and security protocols, ensuring that systems are understandable and maintainable over time.

To create strong documentation standards, start with a clear, organized approach to recording information about the database system and its data. This includes:

• Database schema and data models: Detailed descriptions of the database schema, data models, and relationships among data entities. You should include diagrams where applicable to provide visual representations of the system.

• Code documentation: Inline comments and external documentation for stored procedures, functions, triggers, and any custom code. This ensures that the purpose and logic behind code are easily understood by new and existing team members.

• Configuration and deployment guides: Instructions for setting up, configuring, and deploying the database environment, including any third-party tools or extensions used within the system.

Multiple levels of documentation

Documentation should address various aspects of the data management system at multiple levels, including:

• Technical documentation: Aimed at developers and database administrators, detailing the technical specifics of the database system, codebase, and infrastructure.

• User documentation: Targeted towards end users, providing guides on how to access and use the data, including any applications or tools developed for data analysis and reporting.

• Policy and procedure manuals: Describing the policies governing data use, security measures, backup and recovery processes, and procedures for routine and exceptional tasks.

Invest in training and maintenance

Documentation is not a one-time effort but requires ongoing maintenance and updates to remain relevant and useful. Investing in regular reviews and updates of documentation ensures that it keeps pace with changes in the database system, data models, and business requirements. Additionally, training for team members on effectively using and contributing to documentation promotes a culture of knowledge sharing and collaboration.

• Training programs: Implement training sessions for new hires and refresher courses for existing team members to familiarize them with the documentation practices and standards.

• Documentation maintenance plan: Establish a schedule for regularly reviewing and updating documentation to ensure accuracy and completeness. This can include assigning responsibility to specific team members or groups for different sections of the documentation.

Automation

Automation is key to saving valuable development time, allowing teams to focus on more critical areas of data management. It streamlines repetitive tasks and enhances the scalability and reliability of the foundational pillars of data management.

• Automating data pipelines: This keeps systems productive and reliable by ensuring data is accurately and timely processed, reducing the risk of human errors.

• Automated governance: By managing metadata for large systems, automation supports consistent policy enforcement and compliance monitoring without manual oversight.

• Automated security: This includes real-time threat detection, automated patching, and recovery processes, enhancing the safety and accessibility of data systems.

• AI in documentation: Generative AI can transform code documentation, making it more efficient and standardized. AI can streamline documentation by generating it alongside new projects and updating it for legacy systems, saving time and ensuring consistency.

Data Lifecycle Management With Timescale

Data Lifecycle Management (DLM) is crucial in handling the vast volumes of data generated over time, especially for time-series data. DLM involves several key stages:

1. Ingest and store: data is collected and stored efficiently.

2. Recent data query: quick access to the most recent data is ensured.

3. Aggregated rollups: data is summarized over time to facilitate analysis.

4. Archive data: older data is moved to less expensive storage for long-term retention.

5. Delete data: outdated or irrelevant data is securely deleted to manage storage space.

Built on PostgreSQL—but faster—Timescale provides features that enhance each stage of the data lifecycle:

• Hypertables facilitate efficient data ingestion and querying by automating partitioning across time and space dimensions.

• Continuous aggregates allow for real-time data rollups, making data analysis more efficient.

• Columnar compression significantly reduces storage costs for historical data.

• Tiered storage enables data archiving by seamlessly moving older data to cheaper storage solutions.

• Fast deletion with time partition ensures outdated data can be removed quickly and efficiently without impacting system performance.

Let's dig into how each of these features can help you manage your data simpler and more effectively.

Data ingestion with hypertables

A data ingestion system pulls data from a warehouse into a usable form. For example, you can use dbt to query a cloud warehouse with a database abstraction layer.

Timescale ingests data into hypertables. Hypertables are PostgreSQL tables that automatically partition your data by time. This means that they are divided into smaller tables, called chunks, each of which holds data from a specific time range. Partitioning prepares data for efficient queries.

Here are some of the benefits of using hypertables for data ingestion:

• Improved insert and query performance: By partitioning data by time, hypertables can improve the performance of insert and query operations. This is because queries only need to scan the chunks that contain the data they are interested in.

• Easier management of time-series data: Hypertables unlock a number of features that make it easier to manage time-series data, such as automatic partitioning, time-based queries, and continuous aggregates.

Query recent data with continuous aggregates

Especially within time-series databases, the ability to efficiently query recent data is vital. This "recent query" stage is crucial for businesses and analytics applications that need to:

• Incorporate new data into analytics: As new data streams in, it's essential to seamlessly integrate it into existing datasets for comprehensive analysis.

• Run analytics to track the current status: Real-time or near-real-time analytics help organizations monitor their operations, detect anomalies, and make informed decisions promptly.

• Builds value from data streams: By continuously analyzing recent data, organizations can derive actionable insights, identify trends, and improve their services or products.

Leveraging Timescale's continuous aggregates

Timescale's continuous aggregates offer a solution for efficiently managing and querying recent data. These continuous aggregates are somewhat akin to incremental refresh materialized views in standard SQL but are specifically optimized for time-series data.

Here's how they work:

• Similar to incremental refresh materialized views in SQL: As mentioned, continuous aggregates update the aggregate view of data as new information is ingested, similar to how materialized views are refreshed incrementally in SQL databases. However, they are designed with time-series data in mind, offering superior efficiency and flexibility.

• Updates a query while keeping previous calculations cached: This feature ensures that previously computed aggregates are not recalculated with every update. Instead, only the new or changed data is processed and added to the aggregate. This approach significantly reduces the computational overhead, making analytics faster and more cost-effective.

• Time partition allows efficient extension of materialized aggregates: By partitioning data based on time, continuous aggregates can efficiently extend the materialized aggregates with new data. This time-partitioning feature ensures that the database can quickly access and update the relevant portions of the aggregate, further enhancing performance and scalability.

Create aggregated rollups with columnar compression

Aggregated rollups are a pivotal aspect of efficient data management, especially for extensive databases. They allow for the creation of condensed data summaries that reflect significant trends and metrics across the entire dataset. This process not only makes older data readily accessible for analysis without the need for recalculation but also significantly enhances query performance by reducing the data volume that needs to be processed.

Leveraging Timescale for efficient rollup with columnar compression

We introduced a new approach to managing large PostgreSQL databases by building columnar compression within a row-oriented database framework. In this blog post, "Building Columnar Compression for Large PostgreSQL Databases", we go into detail on how we did it, but here are some of the highlights:

• Efficient storage and access: The necessity for querying extensive databases demands an optimized storage solution that remains accessible. Columnar compression addresses this by significantly reducing storage space and improving query performance without sacrificing data integrity.

• Partitioning and compression: We created a partitioning system that compresses individual columns according to their data type. This selective compression strategy is crucial for maintaining high efficiency, as it allows for the tailored application of compression algorithms to optimize storage and retrieval processes based on the nature of the data.

By enabling Timescale's efficient rollup and compression, you can enhance the performance of your large-scale PostgreSQL databases, leveraging a scalable solution to the challenges of managing vast datasets.

Archive old data with tiered storage

Archiving old data is a critical aspect of database management, especially for systems handling large volumes of information over time. As data ages, it often becomes less relevant for immediate access but still holds value for historical analysis or regulatory compliance.

Developers can move this older data to slower, more cost-effective storage solutions to optimize performance and reduce costs. This process ensures that the database's primary storage remains fast and responsive for current operations while still retaining access to historical data at a lower cost.

Archive system overview

In many database systems, including PostgreSQL environments, archiving old data involves moving it from primary storage to a secondary storage tier. This tiered storage approach is based on the principle that not all data requires the same level of accessibility.

As data becomes older and less frequently accessed, it can be relocated to slower, cheaper storage media. This strategy helps manage storage costs effectively while keeping the system's performance optimized for the most relevant and frequently accessed data.

Timescale tiered storage

To help you save money while still being able to access your old, infrequently used data, we created tiered storage (only available for our cloud services). This multi-tiered storage backend enables the automatic shifting of old data to less expensive storage tiers.

This process is facilitated by the database's time-partitioning capabilities, which organize data into partitions based on time. As data in older partitions is accessed less frequently, it can be automatically moved to a secondary storage tier, such as slower disk drives or cloud object storage, which are more cost-effective.

The key advantages of Timescale's tiered storage include:

• Automatic data movement: Leveraging time-partitioning, you can now automate the process of moving old data to different storage tiers based on predefined criteria, such as the age of the data. This automation simplifies management and ensures that data is stored in the most cost-effective manner without manual intervention.

• Cost savings: By storing older, less frequently accessed data on cheaper storage, you can significantly reduce storage costs. This approach allows for allocating high-performance, more expensive storage resources to only the most critical data.

• Performance optimization: Keeping only the most frequently accessed data on the fastest storage media helps you maintain optimal database performance. Query times are improved as the system does not need to sift through large volumes of historical data stored on the primary storage tier.

• Accessibility: Despite being stored on slower, more cost-effective storage, archived data remains accessible for queries and analysis. This ensures that businesses can still derive value from their historical data without compromising on performance for current operations.

• Flat fixed price: Our low-cost storage tier has a flat price of $0.021 per GB/month for data—cheaper than Amazon S3.

Drop expired data with partitioned tablespace

We've seen how managing the data lifecycle is crucial for maintaining database performance and storage efficiency. One aspect of this management involves removing data that is no longer necessary or valuable to store. This could be due to data reaching a certain age, becoming irrelevant, or simply to comply with data retention policies. Efficiently dropping expired data ensures that storage resources are optimized and costs are kept in check.

Data drop system overview

A robust data drop system automates the removal of unnecessary data based on established criteria. This could involve data age, specific conditions met by the data, or regulatory requirements for data deletion. Automating this process helps maintain a lean database environment, focusing storage and performance resources on data that provides value.

TimescaleDB's approach to fast data deletion

By leveraging its time-partitioning capabilities, TimescaleDB offers a highly efficient way to drop expired data through partitioned tablespaces. Since data is organized into chunks, each chunk is a set of time-partitioned records. These chunks are stored as separate tables within the PostgreSQL tablespace.

This structure significantly simplifies the deletion process:

• Chunk-based deletion: Instead of marking individual records for deletion and later performing a cleanup operation (which is the standard approach in many SQL databases), Timescale can drop entire chunks of data in one operation. This is akin to executing a DROP TABLE command, instantly freeing up the storage space that the chunk occupied.

• Efficiency and performance: By dropping data at the chunk level, Timescale avoids the overhead associated with row-by-row deletion operations. There's no need to vacuum the tablespace to reclaim space post-deletion, as the entire chunk's storage is immediately reclaimed. This approach not only speeds up the data deletion process but also minimizes the impact on database performance during cleanup operations.

• Automated data lifecycle management: Timescale's partitioning system allows for the automation of data expiration and deletion. Administrators can define policies that automatically drop data chunks once they reach a certain age, ensuring that the database only retains relevant data without manual intervention.

Conclusion

In this article, we've navigated through essential best practices for managing PostgreSQL data, spotlighting how Timescale enhances these practices for time-series data management. With specialized features like hypertables, continuous aggregates, and tiered storage, each designed to streamline the data lifecycle from ingestion to deletion, Timescale helps you optimize both performance and cost efficiency.

By integrating Timescale into your data management strategy, you gain:

• Enhanced efficiency with advanced time-series data handling.

• Improved security and compliance through automated data lifecycle management.

• Reduced manual effort with automation of routine tasks, freeing up time for strategic initiatives.

Interested in managing your time-series data with Timescale? Sign up for a free trial.