MongoDB is a C++-based open-source NoSQL database. It’s a dynamic database that stores data in the form of key-value pairs called JSON documents. Each JSON document has two components: tags and data. The tag is a unique id that also contains meta-information.
Engineers often call MongoDB a schemaless database because it doesn’t work on the concept of tables and fields like other RDBMS. Since the schema isn’t defined, there are no constraints on the input data. As a result, a single collection can include several documents, each having its own fields and content. Due to this, MongoDB databases are more flexible.
Hiring Guide
Along with a key, MongoDB also has different kinds of indexes. It uses single, compound, multi-key, and hashed indexes. It also offers geo indexing for geometric queries. You can also use Index intersection, i.e., using multiple indexes for a single query. These indexes can sort queries and create sub queries to ensure selectivity. This makes the overall search process efficient and quick.
MongoDB allows aggregations or grouping of data from different sources to return a single result. It has 3 stages: match, group, and sort. The match stage allows you to filter those exact documents that you need to work with, removing those that don’t fit your requirements.
The group stage allows you to change queries as needed. You can also carry the result of your collection into a new group. Later you can sort the result according to specific fields. You can also limit the documents and increase them if required.
Popularity of MongoDB in Today’s Market
MongoDB is the most popular NoSQL database and it’s well-known to businesses around the world. Today many companies are using this open-source database for their applications/data storage. As per this survey, approximately 5,000+ companies have acknowledged they use MongoDB. Companies such as IBM, Citrix, and Twitter are among the most notable names.
MongoDB offers horizontal scalability via sharding and replica sets. The data is divided into shards (different nodes) using a shard key. Shard balancing is done to ensure that each cluster has an equal number of nodes.
MongoDB supports high availability and redundancy through replication sets. This process produces numerous copies of the data and then distributes the copies to various servers. If one server fails, the secondary server becomes the primary server via election, and you can access a copy of the data through it. In addition, you can use MongoDB Atlas for quick scaling.
MongoDB’s performance is also top-notch. It uses locking to ensure data concurrency, and features like aggregation and advanced indexing allow it to fetch results quickly.
Challenges Tech-Companies face when hiring MongoDB Developers.
A skilled MondoDb developer is an asset to your business. They can develop specialized MongoDB-based products and create software that matches your business requirements. They can also improve the scaling and performance of your current systems. The issue is, not many individuals are knowledgeable or qualified enough to work in companies.
Sometimes the engineer may not be able to work on complex ETL projects, or they might not be able to get meaningful output through data. In addition, database management skills don’t necessarily translate to platform expertise.
Many developers don’t consider emerging technologies and software trends while working on their company’s data. A MongoDB developer has to keep up to date with the latest technology like AI and machine learning to ensure that the company’s tech stack is updated to handle new datasets.
How to Choose a Perfect MongoDB Developer?
Hiring a MongoDB developer is a complex task. A perfect MongoDB developer should also be able to convert business needs into technical specifications and design efficient and scalable solutions using those standards.
They should also know how NoSQL databases work as well as be able to use other MongoDB resources such as Atlas and Developer’s Hub.
A MongoDB developer might have to work on backup and recovery, so they should know about the database’s backup techniques. They should also be well versed with REST API management and standard development frameworks such as Agile and SCRUM.
Interview Questions
Explain the use of profiler in MongoDB
The profiler gathers information on database, configuration, and administration commands running on a particular instance of MongoDB. Then, the profiler saves all of the information it gathers to the capped system collection for user knowledge and recollection.
What is oplog(Operational log)?
The operational log is a restricted collection that records all the operations performed on that database.
Whenever you perform a database operation in MongoDB, it’s first applied to the primary member, and the secondary member performs subsequent replication based on the primary’s oplog. Once oplog reaches its capacity, the oldest entries are overridden to make way for the new ones.
Explain the Mongo Shell
It’s a JavaScript interface that you can use to interact with a MongoDB instance. Through it, you can perform administrative tasks, including issuing queries to update document data.
Does MongoDB need a lot of RAM to run?
Not necessarily. MongoDB can run on a small amount of RAM too. MongoDB can dynamically allocate and deallocate RAM based on system requirements. For processing 100,000 assets, it uses around 1GB of RAM.
What is a Storage Engine in MongoDB?
It’s a MongoDB component that manages data storage in memory and disk. Based on your specific workload requirements, you can choose from the different storage engine options that MongoDB provides. The default storage engine is WiredTiger. Another example of the MongoDB storage engine is the In-memory Storage Engine.
Job Description
We are looking for smart MongoDB developers to join our global team. They should be passionate team players who specialize in software development, database handling, and maintenance. It’s an excellent opportunity for result-oriented developers who want to work on new technologies and ensure database reliability, availability, and security.
Responsibilities
- Configure MongoDB.
- Implement and maintain the best MongoDB practices for indexing and aggregation.
- Research and perform complex tasks based on business requirements.
- Ensure database reliability, security, and performance.
- Perform database backup and recovery. Should be able to implement software patches.
- Coordinate with product managers, DBAs, and stakeholders to understand business requirements.
- Work on documentation and participate in Agile meetings.
- Follow best industry practices and standards.
- {{Add other relevant responsibilities}}
Skills and Qualifications
- Working Knowledge of MongoDB and its platform.
- Experience in optimizing insertions and designing database systems for large datasets.
- Proven experience with load balancing, aggregation, and disaster recovery
- Knowledge of JSON and server management.
- Knowledge of REST API and architecture design.
- Problem-solving skills and team spirit.
- {{Add other frameworks or libraries related to your development stack}}
- {{List education level or certification required}}
Conclusion
MongoDB is a user-friendly database that has a lot of potential. Many companies are now building MongoDB projects and working with NoSQL databases instead of traditional RDBMS. MongoDB developers don’t just maintain databases but also extract insights and analytics for important decision-making. Hence you should be very careful who you hire as a MongoDB developer/admin.
