Choosing MongoDB or PostgreSQL: A Guide to Database Solutions

Compare NoSQL and SQL databases to determine the ideal solution for your data needs

The Database Dilemma: MongoDB vs. Postgres

The importance of selecting the best database for your organization

​When deciding on a database management system, organizations often have to choose between SQL and NoSQL, making it essential to select the right database based on specific use cases.

Developed in 2009, MongoDB is a NoSQL document-oriented database designed to accommodate large volumes of unstructured data. Its primary use cases include applications that require high scalability and flexibility, such as content management systems, mobile applications, and real-time analytics, where data structures might change frequently and rapidly.

MongoDB follows a mixed licensing structure – part open source, part proprietary – which may require additional expenses for organizations needing the advanced features and support available in its proprietary versions. ​

Conversely, PostgreSQL, founded in 1986 as a relational database, is renowned for its robustness; atomicity, consistency, isolation, and durability (ACID) compliance; and support for complex queries. It excels in scenarios where data integrity and structured relationships are key, making it an ideal choice for applications in finance, enterprise content management, and any environment that demands rigorous transactional support.

​The open source nature of PostgreSQL and absence of licensing fees enables businesses to innovate freely and fosters a collaborative development atmosphere. A diverse group of developers can contribute enhancements and share improvements.

As these databases cater to different data models and operational requirements, understanding their origins and typical applications is pivotal in order for organizations to make a decision.

Data Models: Document-Based vs. Relational

The core differences between how MongoDB and PostgreSQL handle data

MongoDB and PostgreSQL differ greatly in their data models: MongoDB is document-based, while PostgreSQL uses a traditional relational model.​

In MongoDB, data is stored in flexible, JSON-like documents, allowing for a schema-less design in which different documents in the same collection can have varying structures. This flexibility makes MongoDB advantageous for applications that experience frequent changes in requirements, such as agile development environments or those dealing with large amounts of unstructured data.

In contrast, PostgreSQL organizes data into structured tables with defined schemas, adhering to strict ACID compliance that ensures data integrity and reliability. This structure supports advanced querying capabilities and encourages complex relationships between data entities through foreign keys and joins. This makes PostgreSQL a preferred choice for applications that require robust data integrity and consistency, such as financial systems or enterprise resource planning.

MongoDB’s document-based approach offers significant advantages, including scalability and speed when dealing with large datasets, plus ease of horizontal scaling across distributed systems. However, this model can lead to challenges in relationships between data as well as potential redundancies.

On the other hand, while PostgreSQL’s relational model excels in ensuring data integrity and supporting complex queries, it can be less adaptable to rapidly changing data requirements.

Notable users of MongoDB include major players such as eBay, Uber, and Lyft, which rely on its capabilities to handle massive volumes of data while providing fast read and write operations. Organizations including Apple, Skype, and Instagram utilize PostgreSQL to ensure that their backend databases maintain consistency and reliability during transactions.

Performance and Scalability: How MongoDB and Postgres Compare

Learn more about joins, sharding, and other optimization techniques

The performance and scalability of database management systems are critical for organizations managing and analyzing large volumes of data. PostgreSQL and MongoDB present distinct advantages and challenges that cater to different application needs.

PostgreSQL is renowned for its robust performance in handling large-scale transactions while maintaining full ACID compliance. This quality makes it a preferred choice for applications in which data integrity and complex transactional capabilities are crucial, such as financial systems or enterprise resource planning. PostgreSQL supports advanced features such as multi-version concurrency control (MVCC), allowing it to efficiently manage simultaneous user transactions without data conflicts.

The database also benefits from powerful optimization techniques that enhance complex queries’ performance, including multi-table join operations that can aggregate and manipulate vast datasets. PostgreSQL employs various join strategies, such as nested loop, hash join, and merge join, with the chosen method directly impacting the query execution time.

​Read replicas in PostgreSQL also offer significant advantages. By offloading read queries to multiple replicas, organizations can reduce the workload on the primary database, which in turn improves response times for users and prevents bottlenecks during peak usage periods. Additionally, read replicas provide an extra layer of fault tolerance; if the primary database fails, one of the replicas can be promoted to become the new primary, ensuring continued access to data and minimizing downtime.

MongoDB, on the other hand, excels in scenarios requiring horizontal scalability and flexibility in handling unstructured data. Its document-oriented architecture makes it adept at managing varied data structures without needing a fixed schema. This flexibility facilitates rapid application development and iteration, which is beneficial in environments where the data structure may frequently evolve. MongoDB’s horizontal scaling capabilities are achieved through sharding, where data is partitioned across multiple servers. This design distributes the load effectively and enhances performance by allowing simultaneous reads and writes.

When it comes to scalability, PostgreSQL employs both vertical and horizontal strategies. Vertical scaling involves upgrading server resources such as CPU, memory, and storage, which can improve performance for transactional workloads. On the other hand, horizontal scaling can be more complex in PostgreSQL and often requires extensions or third-party solutions to implement sharding effectively. Nevertheless, PostgreSQL can utilize table partitioning, which divides large tables into smaller, more manageable sections. This reduces the amount of data scanned at any given time during operations.

​In sum, while PostgreSQL shines in managing large transactions with rigorous ACID compliance, complex queries, efficient join operations, and read replicas, MongoDB offers superior capabilities for horizontal scaling and managing unstructured data.​

Use Cases: When to Choose MongoDB vs. PostgreSQL

Scenarios where each database excels, from financial transactions to high-velocity applications

When choosing between MongoDB and PostgreSQL, understanding specific use cases can greatly influence the decision.

In the financial services sector, PostgreSQL is selected for its robust ACID compliance. Banking systems and trading platforms rely on PostgreSQL to maintain precise transactional records and audit trails, minimizing the risk of data corruption or discrepancies.

Additionally, PostgreSQL’s relational model effectively manages the interdependencies of financial data. Its use of structured tables and support for advanced SQL features, including joins and foreign keys, allow powerful data manipulation and retrieval techniques, enabling financial institutions to run complex queries efficiently for reporting and analysis. This makes PostgreSQL particularly well suited for finance applications.

PostgreSQL also finds its place in enterprise resource planning (ERP) systems. These systems require structured data management with strict relationships among entities, such as customers, orders, and inventory. PostgreSQL’s strong typing system and support for advanced querying capabilities allow organizations to maintain accurate and consistent data.

Conversely, MongoDB is preferred for applications dealing with high-velocity, unstructured, or semi-structured data. For example, in the realm of the Internet of Things (IoT), MongoDB’s document-based architecture allows easy storage and management of the diverse data generated by various IoT devices. Additionally, MongoDB’s horizontal scalability makes it a strong candidate for applications that must accommodate rapid data growth, as it allows data to be distributed across multiple servers seamlessly.

Another scenario in which MongoDB excels is in content management systems (CMS). MongoDB’s schema-less design provides the necessary agility in CMS applications, where content types often evolve and require rapid updates. Organizations such as Forbes have successfully implemented MongoDB to enhance content delivery, enabling editors to improve engagement rates by publishing updates quickly and efficiently.

Ecosystem and Tooling: Supporting Infrastructure

Comparing MongoDB and PostgreSQL’s tools, support services, and more

The ecosystems surrounding MongoDB and PostgreSQL are rich and varied, offering a range of tools and community support that cater to their respective user bases.

PostgreSQL boasts a comprehensive ecosystem with a wealth of tools specifically designed for data analysis and replication and many extensions that significantly enhance its capabilities. This extensive suite includes platforms such as ART (A Reporting Tool) for reporting and business intelligence, and libraries including PostgresML for machine learning applications within the database environment. Such tools empower organizations to perform advanced analytics directly on their data stored in PostgreSQL, making it an excellent choice for applications requiring complex reporting and data-driven decision-making.

PostgreSQL’s built-in replication capabilities and tools such as repmgr facilitate robust data protection and high availability. These tools allow users to easily manage and monitor replication setups, ensuring data redundancy and consistency across multiple instances. PostgreSQL’s support for various extensions further enhances its functionality, enabling users to tailor the database environment to their needs. Notable extensions such as PostGIS provide geographic capabilities, while pg_partman aids in managing data partitioning, allowing PostgreSQL to handle large datasets efficiently.

​PostgreSQL also excels in the cloud-native world with the support of CloudNativePG, a Kubernetes-native operator designed specifically for managing PostgreSQL databases in cloud environments.​ This integration provides features such as automated failover, high availability, and seamless backup management.

Meanwhile, MongoDB also shines in the cloud-native development realm; its document-oriented data model aligns well with applications requiring rapid iteration and frequent schema changes. MongoDB Atlas, the fully managed cloud database service, simplifies deployment and scaling processes, allowing developers to focus on building applications rather than managing infrastructure. The cloud-native tools and integrations that MongoDB offers, such as seamless compatibility with Kubernetes for orchestration and various development environments, enable organizations to maintain agility and respond swiftly to evolving market demands.

Furthermore, MongoDB’s extensive ecosystem supports a variety of libraries, tools, and frameworks tailored for handling JSON documents and facilitating efficient data storage and retrieval. This ecosystem is beneficial for applications in dynamic environments, such as IoT and content management systems, where data structure may change frequently. The community backing MongoDB is robust, with various user groups and forums providing platforms for developers to share insights, resolve issues, and collaborate on best practices.

How PostgreSQL and MongoDB address security and compliance concerns for various industries

PostgreSQL and MongoDB adopt different access control and auditing methodologies.

PostgreSQL utilizes a robust role-based access control (RBAC) system, which allows administrators to create roles that can be assigned specific permissions on database objects. This simplifies user access management and also introduces fine-grained controls, including row-level security (RLS). RLS enables administrators to define policies restricting access to individual rows based on user attributes, thereby providing enhanced data protection in environments with multiple user types. Additionally, PostgreSQL supports detailed logging capabilities through extensions such as pgAudit, which allows extensive auditing of user actions and modifications, ensuring compliance with various regulatory standards.

In contrast, MongoDB also employs RBAC but emphasizes flexibility, which is suited to its document-oriented design. MongoDB users are assigned roles that determine their access permissions, ranging from read-only to full administrative rights. The granularity of these roles allows easier adaptation to dynamic application requirements. MongoDB’s auditing capabilities facilitate the logging of significant database operations, providing transparency for compliance with regulations. While MongoDB’s auditing features are comprehensive, they are primarily available in the Enterprise edition, focusing on the operations performed or administrative changes made rather than providing the level of detail that PostgreSQL offers.

​Regarding security features, PostgreSQL is renowned for its stringent compliance capabilities, making it particularly appealing in finance and government sectors.​ Its comprehensive access control mechanisms, granular permissions, and robust auditing features align well with regulatory requirements such as PCI DSS and GDPR. PostgreSQL’s encryption capabilities protect sensitive data at rest and in transit, and detailed audit trails track data access and modifications, which are vital for regulatory inspections.

On the other hand, MongoDB has made significant advancements in security, particularly with its cloud-native solutions such as MongoDB Atlas. This platform offers built-in security controls, such as encryption for data in transit using TLS and encryption at rest. MongoDB’s architecture enables organizations to meet compliance regulations while handling large volumes of unstructured data, which is common in the IoT and healthcare sectors. However, while MongoDB can effectively secure data, its auditing capabilities may not provide the same depth of detail as PostgreSQL, potentially affecting its applicability for industries that require exhaustive tracking and documentation.

Cost and Licensing: Open Source vs. Proprietary Considerations

PostgreSQL’s open source advantages vs. MongoDB’s mixed model

PostgreSQL and MongoDB present contrasting cost and licensing models, reflecting their foundational philosophies and business strategies.

PostgreSQL operates under a liberal open source license, specifically the PostgreSQL License, which allows users to freely use, modify, and distribute the software without licensing fees. Users can scale their deployments without the limitations typically imposed by proprietary software, making it an attractive option for companies looking to manage expenses while maintaining robust database capabilities.

In contrast, MongoDB employs a mixed licensing model that includes open source and proprietary elements. MongoDB Community Server is available under the Server Side Public License (SSPL), which permits free use, modification, and redistribution; however, it includes specific restrictions that prevent using it as a service without releasing the source code of the offering. This nuance can deter some organizations from fully leveraging Community Server for commercial applications. MongoDB also offers a paid Enterprise version and MongoDB Atlas, a fully managed cloud database service with a usage-based pricing model for businesses seeking additional features, performance, and support. While the community edition provides essential functionality, many enterprises may find the paid versions necessary for compliance, security, and advanced capabilities.

The open source nature of PostgreSQL confers several significant advantages, particularly with flexibility, transparency, and community support. Being free from licensing fees allows businesses to innovate and allocate resources as needed without worrying about escalating costs associated with database usage. Furthermore, PostgreSQL’s permissive licensing encourages a collaborative development environment, enabling a diverse community of developers to contribute enhancements and share improvements, ultimately bolstering the software’s robustness and feature set.

PostgreSQL’s extensive support for various extensions and tools enhances its appeal. Organizations can customize their database setup to fit specific needs without incurring extra costs, a capability often restricted in proprietary systems. This open approach fosters an ecosystem where users can adapt and evolve their database solutions in response to changing needs or technological advancements.

Conversely, while MongoDB offers flexibility through its Community Server, the mixed license structure introduces complexities that can lead to higher overall costs, particularly for organizations requiring the advanced features and support in its proprietary offerings. As companies scale, they may face additional costs associated with cloud services and proprietary licenses, complicating budget management.

EDB: Why PostgreSQL Might Be the Right Choice for You

Why PostgreSQL, enhanced by EDB, can offer the scalability, security, and support your organization needs

As the adoption of PostgreSQL has grown, EnterpriseDB (EDB) has positioned itself as a leader in providing enterprise-grade enhancements and services, enabling organizations to leverage the full potential of PostgreSQL while addressing the complexities of large-scale deployments. EDB’s solutions include advanced features for performance optimization, high availability, and security, making it easier for enterprises to implement PostgreSQL in mission-critical environments.

One of the key advantages of choosing PostgreSQL is its ability to scale efficiently and meet growing data needs. EDB’s tools facilitate seamless scaling options, ensuring that organizations can manage increasing workloads without sacrificing performance. This scalability is critical for businesses experiencing rapid growth or those needing to accommodate real-time fluctuating demands. Additionally, EDB’s focus on security measures, such as advanced authentication methods and transparent data encryption, provides an extra layer of protection paramount in industries handling sensitive information.

Moreover, the talent pool for PostgreSQL is generally larger than for MongoDB, which can be a significant consideration for organizations concerned about recruiting and training qualified personnel. PostgreSQL has established itself as a widely recognized database solution; many database professionals already possess the necessary skills and knowledge to work with it, making it easier for companies to find and onboard talent. In contrast, the more niche nature of MongoDB can present challenges in hiring and training, potentially leading to extended onboarding periods and higher staff development costs.

EDB’s expertise in guiding organizations through the transition to PostgreSQL is another compelling reason to consider this database for enterprise needs. The company’s team of experts can provide strategic consulting and support to ensure that organizations not only migrate smoothly but also optimize their PostgreSQL installations for maximum performance. By leveraging EDB’s resources, companies can benefit from tailored solutions that address specific operational requirements while ensuring that best practices are followed during implementation.

NoSQL vs. SQL: Content and Resources

Compare database types further with the following resources

NoSQL gained popularity when it first came out in the late ’90s. Is the reception to non-relational databases still the same today?


Some NoSQL vendors tout the benefits of the “schema later” approach. EDB’s Michael Stonebraker shares his thoughts.


Postgres expert Bruce Momjian discusses SQL vs. NoSQL and more on the Linux Inlaws podcast.


Enjoy Robust Cloud Database Solutions with EDB

Harness the power of PostgreSQL for strong data integrity and complex transactions

PostgreSQL offers significant advantages over other database types, including advanced querying, stringent security, and reduced costs. Let EDB optimize your PostgreSQL capabilities further with expert tools, services, and 24x7 support. Start your free trial now.

What are the differences between MongoDB and PostgreSQL? chevron_right

MongoDB is a document-oriented database that offers flexibility in data structures and scales horizontally, making it suitable for applications needing rapid changes and complex data types. In contrast, PostgreSQL is a relational database that relies on a structured schema and uses SQL for data management, excelling in handling complex queries and transactions. ​The choice between them often depends on whether the application requires a schema-less design for diverse data or a structured, relational approach with robust ACID compliance.

Which is better for large-scale applications, MongoDB or Postgres? chevron_right

PostgreSQL is the better choice for large-scale applications due to its robust support for complex transactions, advanced querying capabilities, and strong data integrity through ACID compliance​. Its ability to handle structured data effectively, combined with table partitioning and powerful indexing, enables it to manage extensive datasets while maintaining performance and reliability, which are crucial for enterprise-level applications. While MongoDB offers flexibility, PostgreSQL’s proven architecture and extensive feature set make it more suitable for applications requiring rigorous data management and consistency, especially in environments with prevalent complex data relationships.

Is MongoDB or Postgres better for unstructured data? chevron_right

​MongoDB is better suited for unstructured data because it utilizes a document-based model that allows flexibility in storing and accessing data.​ This model enables developers to work with data in various formats without needing predefined schema, making it easy to accommodate changes and variations over time. Additionally, MongoDB’s ability to store data as JSON-like documents supports hierarchical structures, which is advantageous for applications that manage complex and varied data types. In contrast, PostgreSQL, a relational database, requires a fixed schema that can be restrictive in environments with unstructured data.

How does security compare between MongoDB and Postgres? chevron_right

Security measures in PostgreSQL are generally considered to be more advanced and comprehensive than MongoDB’s, largely due to its maturity as a relational database and its extensive access controls, role-based permissions, and robust auditing capabilities. PostgreSQL supports features including data encryption at rest and in transit, along with fine-grained access controls, providing high security for sensitive data. In contrast, MongoDB has made significant strides in security, offering features such as authentication, auditing, and encryption. However, its security model is still considered less mature than that of PostgreSQL, particularly for complex enterprise requirements.

What are the cost differences between using MongoDB and Postgres? chevron_right

The cost differences between MongoDB and PostgreSQL primarily stem from their pricing models and deployment options. PostgreSQL is open source and can be run without licensing fees, leading to lower operational costs, especially for self-managed installations. In contrast, while MongoDB offers a free community edition, its more advanced features and managed cloud services, such as MongoDB Atlas, often come with subscription-based pricing that can increase costs based on storage and usage.

What are the advantages of using PostgreSQL over MongoDB? chevron_right

​PostgreSQL offers several advantages over MongoDB, particularly in areas requiring strong data integrity and complex transaction support.​ PostgreSQL provides robust ACID compliance as a relational database, ensuring reliable transaction processing and consistency in data management. It excels at handling complex queries through SQL, enabling powerful data manipulation and analysis capabilities often essential for enterprise applications. Additionally, PostgreSQL supports advanced features such as foreign keys, joins, and constraints, allowing intricate data relationships and integrity that MongoDB’s document model may not handle as effectively. These features make PostgreSQL an ideal choice for applications for which structured data and sophisticated querying are priorities.