November 2016 Summaries

MongoDB queries can fail to include all the matching documents due to concurrent updates that move data from one portion of the index to another, resulting in either overcounting or undercounting. This issue affects queries that use indexes and is more pronounced when multiple documents are updated concurrently. In contrast, Couchbase returns the expected number of qualifying documents even with concurrent updates, thanks to its stable index scans, which provide protection against this issue. To mitigate this problem, developers should design data models that select and update only one document for each query, avoiding multi-document queries in MongoDB.

During a week-long visit to Texas, the author engaged with four user groups to discuss Couchbase, starting with two sessions in Austin. The Austin .NET User Group featured a recording by Shawn Weisfeld from UserGroup.TV, who provided a superior technical setup. The following evening, the author presented to the Austin Node.JS User Group, which drew a large audience and prompted numerous insightful questions. The author encouraged local participation in these groups and shared plans to visit Houston for additional engagements, with more content to be released soon. Updates and insights can be followed on the author's Twitter, @mgroves.

This post serves as the second installment in a series exploring the Couchbase Mobile stack, focusing on the Couchbase Web Console (CWC) to help users get acquainted with the system. It provides an overview of how to navigate the Web Console's interface, specifically emphasizing the Data Buckets panel, which is essential for understanding Couchbase Mobile. The post explains the functionality of the "Documents" and "Views" tabs within the console, detailing how users can view, edit, and manage documents and create static indexes using Views, which utilize a map/reduce approach for faster queries. The post contrasts this with the more flexible but slower N1QL queries and highlights the current lack of N1QL support in Couchbase Lite. Additionally, it offers guidance on experimenting with Views by copying and modifying existing Production Views, and it outlines the series' future topics, including working with Couchbase Server from the command line, exploring Sync Gateway, and integrating a sample app with Couchbase Lite.

When developing a web application, it is crucial to securely store password data in your database, particularly if you handle user accounts without relying on OpenID or similar systems. Passwords should never be stored in plain text, regardless of the perceived security of your servers. Instead, using Bcrypt to hash passwords before saving them offers enhanced protection for user accounts. A video tutorial is available that explains how to implement this method, and it is complemented by an earlier write-up that provides additional insights. For further information and examples, particularly on using the Node.js SDK with Couchbase, developers are encouraged to visit the developer portal.

Matthew Groves provides an overview of using Visual Studio Code (VSC) and the .NET Core SDK to develop applications on Windows, with a particular focus on integrating Couchbase. He outlines the tools and extensions necessary for setting up the development environment, such as the C# extension powered by OmniSharp and the .NET Core NuGet Project Manager, which can be installed directly through VSC. Groves walks through creating a project, adding dependencies, and running a simple "Hello World" program, before demonstrating how to connect to a Couchbase cluster, insert a document asynchronously, and execute a parameterized N1QL query to list electric bills. Although VSC lacks some features of full Visual Studio and tools like ReSharper, Groves finds the transition to .NET Core relatively smooth for Couchbase developers, with the main adjustment being to the new .NET Core tooling. The complete source code for the example is available on GitHub, and Groves invites feedback and questions, offering his assistance to those encountering challenges with .NET, .NET Core, or Couchbase Server.

At the Code Camp NYC conference on October 8, 2016, the speaker shared insights on Full Stack Development with .NET and NoSQL, with the session being recorded and shared on YouTube. The presentation included a .NET sample and a Xamarin Forms sample using Sync Gateway, both of which are accessible on GitHub. The speaker expressed gratitude for the attendees and highlighted the interactive nature of the session, noting it was one of the most engaging presentations of the year. Attendees and interested individuals are encouraged to follow updates on Twitter through the conference's handle @codecampnyc and the speaker's handle @mgroves.

The video tutorial provides a guide on setting up and developing a Java application that interacts with Couchbase Server to store and query NoSQL JSON data. It suggests visiting the Couchbase developer portal for further details on using the Couchbase Java SDK and recommends tutorials for setting up Couchbase Server on various platforms, including Ubuntu, Windows, Mac, and Docker.

The author of the blog post uses Docker containers to simulate a Couchbase Server cluster locally, allowing them to test and demonstrate various aspects of their ASP.NET Core website. To get started, they recommend installing Docker for Windows, Visual Studio 2015 or later, .NET Core VS 2015 tooling preview 2 or higher, and Visual Studio Tools for Docker. They then run Couchbase Server containers using the `docker run` command, exposing port 8091 to use the Couchbase Console from a web browser at localhost:8091. The author creates multiple Couchbase Server containers and enables replication on one of them, adding it to the cluster by clicking "Add Server" in the Couchbase Console. Once the cluster is set up, they create an ASP.NET Core app that uses the CouchbaseNetClient dependency to interact with the Couchbase cluster. They then deploy the ASP.NET Core app in Docker and run it, noting that the aspnetcore Docker image doesn't attach to the 'bridge' Docker network by default. After running the app again, the author notes that the website appears in their browser, and they can view the Couchbase Console to see how the documents are being automatically sharded amongst the nodes and replicas stored in other nodes. They also experiment with auto-failover and shutting down one of the Couchbase nodes to test the cluster's behavior.

Docker 1.12 introduced a new feature allowing health checks to be integrated into the container's image definition, which can also be overridden via the command line. This feature is crucial as it provides a method for the application inside the container to report its health status, rather than just indicating whether the container is up. The Dockerfile for the arungupta/couchbase image includes a health check instruction that verifies the health of the container by executing a command that checks the availability of a Couchbase REST API endpoint every 5 seconds, with a timeout of 3 seconds. If the health check command fails, the container's status is marked as unhealthy, and Docker's exit status reflects this, with 0 indicating a healthy container and 1 indicating an unhealthy one. Users can also specify health check commands at runtime using the docker run command if the image does not include a HEALTHCHECK instruction. This feature enhances container management by allowing users to monitor the health status of their applications more effectively.

The Couchbase team has introduced support for Couchbase Analytics queries in their Node.js SDK, allowing developers to perform complex analytics on large datasets. This new feature provides direct access to the data management platform, enabling developers to build custom dashboards and reporting tools using industry-standard analysis platforms like Tableau and QlikView. A demonstration application has been built to showcase the capabilities of Couchbase Analytics, including a server-side component that exposes a RESTful interface and a client-side component that displays business-specific metrics in a simple HTML5 page with graphs. The dashboard is powered by Chart.js and uses SQL++ queries to fetch data from the Couchbase Analytics cluster, providing a flexible way for developers to analyze their data and gain insights into their applications.

Couchbase has announced the first Developer Preview of Couchbase Analytics, which introduces parallel data management to Couchbase Server, expanding its query capabilities without sacrificing agility, speed, and elasticity. This preview version operates alongside Couchbase Server, synchronizing with the data service via DCP while remaining standalone, with future plans for full integration to act as a standard Couchbase service. Designed to efficiently handle complex queries involving large ad hoc join, set, aggregation, and grouping operations, Couchbase Analytics supports truly ad hoc queries in reasonable timeframes, even without secondary indexes, by utilizing parallel query processing and bulk data handling. It maintains a common data model, ensuring workload isolation and high data freshness, and uses the SQL++ query language, a modern extension of SQL suited for NoSQL systems. Although SQL++ and N1QL differ, they are expected to merge into a single query language for Couchbase Server in the future. Couchbase encourages engagement and feedback at the Couchbase Connect event, where attendees can learn more about these developments.

Couchbase Server 4.6 introduces significant enhancements to its Full-Text Search (FTS) capabilities, offering performance improvements, custom index type mapping by key, and custom sorting options. The update features MossStore, a new default key-value store mechanism that boosts speed and efficiency by sorting index segments in memory before persisting them. This release enables developers to create custom index mappings using document keys to determine types, facilitating a common data modeling style where document type is indicated by key prefixes. Users can now sort search results by any indexed document field, providing more tailored search results beyond the default sorting by relevance score. Although FTS remains in developer preview, users are encouraged to explore these improvements and provide feedback to influence future development.

Couchbase Server 4.6.0 Developer Preview introduces a range of new features and enhancements across various functionalities, including cross datacenter replication, security, query optimizations, data manipulation tools, and full-text search capabilities. A key highlight is the introduction of a timestamp-based conflict resolution for cross datacenter replication, allowing for the seamless resolution of document conflicts by comparing timestamps. The release also enhances security with pluggable authentication modules for centralized password management, although this feature is limited to Linux platforms and enterprise users. N1QL, Couchbase's query language, sees significant updates with new functions for manipulating date/time values and string tokenization, alongside performance optimizations. Data import and export are streamlined with new tools for handling CSV and JSON files, and full-text search capabilities are bolstered with faster indexing and query processes, customizable sorting options, and improved index type mapping. The release supports new operating systems, including MAC OSX Sierra and Windows 10 Anniversary Edition, and performance improvements are also made to the full-text search engine and its underlying library, bleve.

The script consumes Couchbase metrics via its REST API and command-line tools to digest the health and performance of a cluster on a regular basis. It captures information about each node's health, including its view of the cluster, and stores this data in a Couchbase bucket using N1QL queries. The goal is to provide a simple implementation that can be leveraged by devops teams to diagnose issues in "war room" settings. The script uses Python as a familiar language for generalization and captures specific statistics such as memory utilization and drain queue metrics, which are important for monitoring a Couchbase cluster. The data is stored in a JSON document with a TTL of 30 days, allowing for easy querying and analysis using N1QL queries.

The release of Couchbase .NET SDK version 2.3.9 introduces a mix of new features and bug fixes, including a Data Structure API and Cluster Level Authentication and Query support. This update enhances the developer experience by incorporating Couchbase-backed JSON structures for common data types like sets and lists, facilitating automatic state persistence. A significant change is the shift from bucket-level to cluster-level authentication, enabling more efficient credential management. The update also allows executing N1QL queries directly through the Cluster object, streamlining the process by removing the need for bucket-specific contexts. Furthermore, improvements in Full Text Search (FTS) support and various bug fixes are included to ensure readiness for Couchbase Server 4.6. The release follows semantic versioning, with features subject to stability enhancements in future releases.

The twelfth episode of The NoSQL Database Podcast, available on platforms like TuneIn, iTunes, Pocket Casts, and Stitcher, features a discussion with Google Developer Expert Chris Esplin about using Firebase as an alternative to SQLite in mobile applications. This episode explores the role of Firebase, a back-end as a service (BaaS) by Google, in mobile app development and its place within the NoSQL database landscape. Listeners can access the episode through various podcast networks and are encouraged to forward any questions to [email protected].

In a comprehensive video tutorial, viewers are guided through the process of creating a Golang web application featuring five RESTful API endpoints for performing CRUD operations on a Couchbase database using the SQL-like N1QL query language. By the end of the tutorial, participants should gain confidence in developing Golang applications and integrating Couchbase into their projects. The video builds on concepts introduced in a previous tutorial focused on using Node.js with N1QL, and viewers are encouraged to further enhance their development skills by exploring resources available on the Couchbase developer portal.

Couchbase Community Edition 4.1.1 has been released, enhancing the 4.x series with crucial bug fixes to improve stability. This version is designed to support developers and foster community growth by providing an accessible entry point into Couchbase. While the Community Edition is ideal for exploration and initial use, the Couchbase Server Enterprise Edition is recommended for business-critical use-cases in production environments, offering a more stable and production-ready solution. Users can download the software or review the release notes to begin exploring the new features of the Community Edition.

Pokémon GO's success can be attributed to the scalability of its Pokémon Trainer Club system, which utilized Couchbase Server Enterprise Edition to support millions of users. The choice of NoSQL database allowed for rapid scaling and adaptability, with features like Multi-Dimensional Scaling (MDS) and memory-optimized indexes enabling administrators to isolate and scale discrete services. The team's commitment to support and professional services ensured a smooth launch and resolution of performance issues, with 24/7 support engineers working to resolve problems quickly. By leveraging Couchbase Server's capabilities, The Pokémon Company International was able to manage the growth of its infrastructure incrementally, on demand, and as needed, ultimately supporting the massive user base of the game.

The quickstart video tutorial is designed for Go programmers who are new to Couchbase or NoSQL databases, offering a step-by-step introduction to Couchbase, including exploring complex data models and querying methods. Additional resources are available on the Couchbase Developer Portal, with specific tutorials for installing Couchbase Server on various platforms such as Ubuntu, Windows, and Docker. A user comment highlights an issue with creating an index on Couchbase CE 7.0 beta due to a missing configuration for the Indexer Storage Mode, suggesting a potential area for troubleshooting or further clarification in the tutorial.