The DBA's future as the Database Adviser
With such a large shift towards NoSQL technologies like MongoDB, there is a lot of discussion about the changing role of the Database Administrator (DBA). Many go so far as to say DBAs are no longer needed , an idea driven by new database capabilities that focus on agility with a dynamic schema instead of a fixed schema and features that make operational management easier in areas like high availability and horizontal scaling. Based on my experience working with hundreds of customers to implement MongoDB in their organizations, there is still room for the DBA, even if their everyday tasks might take less time with MongoDB. First, let's talk about the parts of their role that stay the same. There still needs to be someone to set up back-up/recovery processes, handle capacity planning, run maintenance tasks (e.g. upgrades), diagnose issues, do configuration management, and set up replication and sharding. In enterprises, often separate operational teams handle security, monitoring, and diagnosing common issues but that could be part of the DBA's role in some firms as well. Notice I left out schema management; in MongoDB, the implementation of the schema is NOT predefined but is rather determined at the application level and the structure of the object is stored in the application team’s favorite programming language. This is incredibly valuable when business units request new features or data be added to the application. The application developer can simply add it in, and no change needs to be made in the database, enabling rapid agility. In this case, the DBA is no longer the middleman, and can focus on keeping the database up and running. But in some cases, application changes are more complex, and development teams need a database expert to consult about schema design and its impact on performance, maintainability, and other factors. In this case, the role of the DBA transforms into the DB Adviser. In this role, the DB Advisor would work closely with the application development team that implements the schema. The DBA provides the process and due diligence to manage the pace of change rather than enforce the limitations of the relational schema. Implementing the schema in the application might be disconcerting to some DBAs and others out there who rightfully worry about application developers making uninformed decisions and bringing down an application. Letting go of schema management might be a difficult step, but DBAs rely on application developers to make decisions in their application code on a regular basis. Creating a poorly constructed algorithm will bring the system to a crawl and querying fields in unexpected ways would cause performance problems as well. Is choosing schema design in the database so much more responsibility than any other development decision? The DBA should still guide developers, but without the enormous overhead of having to always update a relationship database schema to simply add a field! Your schema should be as dynamic as your business: agile with the optimal amount of control. The DBA has always been the person accountable to ensure the reliability and performance of the database alongside development teams. However, in today's market, the DBA will continue performing most of the activities they do in the former relational-only world, but will advise in other areas to allow their business groups to innovate and iterate faster than their competition. In this shift, the DBAs can take on new roles to help their businesses achieve more, faster. See how you can help your organizations get faster, better and leaner with MongoDB .
Why MongoDB Is Popular
There are many reasons that MongoDB is the most popular non-relational database by far, but one reason stands out across the broad spectrum of customers and users : Agility . I suppose there once was a time when it was acceptable to take months (or years) planning out an application and its associated data schema, building it and then resisting any efforts to update it (because the data infrastructure was so calcified that change was painful if not impossible). We don't live in that time anymore. Particularly in this age of Big Data , we must constantly iterate on our applications as we hone the types of data we're collecting and deploying to improve our user experiences. This is hard to do with a relational database. It's like trying to win the World Series with the Kansas City Royals. Or the English Premiership with Stoke City. It's possible, but unlikely. Iteration is critical to satisfying customers and adapting fast enough to win markets, as noted on the Wide Awake Developers blog : Iteration is [a] fundamental dynamic[[. Iteration facilitates adaptation, and adaptation wins competition. History is littered with the carcasses of "superior" contenders that simply didn't adapt as fast as their victorious challengers. MongoDB enables such iteration. More than any other NoSQL database, and dramatically more than any relational database, MongoDB's document-oriented data model makes it exceptionally easy to add or change fields, among other things. So if a developer needs to quickly evolve an application, MongoDB's flexible data model facilitates this. Rather than fitting an application to meet schema requirements, the developer writes her application and the schema follows. Form follows function in MongoDB, as it were. Yes, MongoDB is popular because it's easy to learn and get started. Yes, it's highly scalable (auto-sharding, anyone?), cost effective and more. But the biggest reason MongoDB is wildly popular, in my experience? Because MongoDB enables profound developer agility through its flexible data model.