NewsBits - The Future of MongoDB and PostgreSQL


Welcome to NewsBits where you'll find the database, cloud, and developer news from around the net for the week ending May 25th.

And now those bits in full.

Database Bits

MongoDB 4.0 RC0 - Over at MongoDB Inc, the first release candidate for MongoDB 4.0 has arrived. 4.0's highlight feature is multi-document transactions, allowing multiple changes to different documents to be committed as a single update. According to the documentation, 4.0 will need new drivers to support this functionality and it will only work within a replica set; you'll have to wait for 4.2 to get transactions across a sharded cluster.

Lesser features include useful new type conversion operators in the aggregation pipeline, a wider scope for change streams to monitor databases or clusters, and support for SCRAM-SHA-256 in authentication.

Enhancements for secondary reads make them non-blocking and there's a claimed 40% faster sharded cluster balancer. There's also tidying up with the removal of the already deprecated MONGODB-CR authentication and the deprecation of the MMAPv1 storage engine. The new release is available to download but obviously, not for production use, only for testing.

PostgreSQL 11 Beta 1 - The PostgreSQL developers have rolled out PostgreSQL 11 Beta 1, ready for it to get some extensive testing in the real world. PostgreSQL 11 is very much a Spinal Tap release; taking the features of 10 and turning them right up. There's big improvements to table partitioning making it more useful. Now records can be updated and moved between partitions, there's support for primary and foreign keys, along with indexes and triggers on partitions too. Hash joins, B-tree index creation and materialized view creation join the club of parallelized operations on PostgreSQL 11 too.

One really useful enhancement is SQL Stored procedures which allow procedures that can encapsulate transactions, instead of as before only being able to be within a transaction. This means a lot more logic can be held server-side for safe execution on demand. Other features include an optional JIT framework to accelerate expression evaluation and the faster application of adding a column to a table with a default value.

As is usual, we'll see a number of betas followed by release candidates as PostgreSQL 11 progresses to final release in "late 2018".

Locking - Understanding Deadlocks in MySQL & PostgreSQL is a good little read if you want to understand the differences and similarities between these two databases and how they lock when there's contention.

MariaDB - MariaDB has announced MariaDB TX 3.0, a combination of the MariaDB database, MariaDB MaxScale clustering and tools. The release sees MariaDB claim Oracle compatibility as a first for open source databases and general availability for MyRocks and Spider storage engines for MariaDB.

Wikipedia - Wikipedia recently had some database downtime, it was handled but the incident report serves as a good lesson on incident response. Initially, the issues hit at the same time as a release was about to take place of code which was assumed to be the cause of the problem and calls to rollback the systems. The confusion was then amplified by the loss of nickname services on the IRC channels the ops team used, converting everyone to a GuestNNN style nick. The lessons? Probably make sure ops know exactly where your deployment processes have got to and make sure your channels of communication are as resilient as you databases.

Cloud Bits

Containerd - The integration of Kubernetes and Containerd is now generally available. Containerd, as the name suggests, manages containers and around six months ago it integrated CRI support to work with Kubernetes. Six months on, and after some removing a layer of the stack to streamline things, Containerd 1.1 has been declared GA, or in other words stable enough for production and integration. For example, the next version of Docker Engine will use Containerd 1.1 and other vendors are planning to roll it out into their cloud platforms soon.

Developer Bits

Bash 5.0 Alpha - Bash has become the ubiquitous default shell on Unix operating systems but it's not standing still. Here's Bash 5.0 Alpha 1 being announced. There's lots of bug fixes in here driven by fuzzing variable handling and getting word splitting to be more POSIXy. There's new variables for command names and epoch times and a smarter history command too; more details in the annoucement.

GitHub - It's the little changes that make all the difference and GitHub users have just had a little change in the search bar on the ubiquitous collaboration platform. The search bar remembers recent teams, projects and repositories now, so tapping '/' will bring up a drop down of that history.

And finally... have you been wondering what to put behind your site? Why not try some Cool Backgrounds where some generated and photographic options are available in an easy to sample front end. Then read down to find the links to the code and tools which generated those visuals.

NewsBits. News in bits, every week at Compose.

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Dj Walker-Morgan
Dj Walker-Morgan was Compose's resident Content Curator, and has been both a developer and writer since Apples came in II flavors and Commodores had Pets. Love this article? Head over to Dj Walker-Morgan’s author page to keep reading.

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