1 Bases de Datos NoSQL

Introduction to NoSQL Databases

What are NoSQL Databases?

• NoSQL databases are defined as those that do not conform to the relational data model, which is structured around tables with rows and columns.

• The term "NoSQL" stands for "not only SQL," indicating that these databases can utilize various data models beyond traditional SQL structures.

Characteristics of NoSQL Databases

• Unlike relational databases, NoSQL databases do not use the entity-relationship model and do not rely on SQL for data access.

• They feature a distributed architecture composed of interconnected nodes, allowing for horizontal scalability.

Data Structure in NoSQL vs. Relational Databases

• In contrast to relational databases that organize data in tables, NoSQL databases use collections where each row corresponds to a document.

• Indexing exists within NoSQL systems but operates differently; operations similar to joins in relational databases are replaced by lookup operations.

Document-Based Storage

JSON Format in Document Stores

• Document-based NoSQL databases store information using JSON (JavaScript Object Notation), which follows a key-value schema.

• Keys act as attributes akin to columns in relational models, while values can include nested documents or arrays.

Advantages of Document-Based Models

• This structure allows for more natural representation of complex data relationships compared to traditional row-column formats.

• A JSON document encapsulates various types of data including strings, nested objects, arrays, integers, and geospatial coordinates.

Popular NoSQL Database Systems

Leading Technologies

• Some widely used NoSQL database systems include Apache Cassandra (developed by Google), CouchDB, Neo4j, Firebase, and MongoDB.

Use Cases and Applications

• These technologies cater to diverse applications ranging from cloud solutions to mobile apps and web services.

When to Choose NoSQL Over Traditional Databases

Key Considerations for Choosing NoSQL

• Organizations may opt for NoSQL when dealing with rapidly growing datasets (terabytes), requiring scalable solutions for increased user loads or distributed architectures.

• Flexibility is another advantage; documents can have varying attributes without strict schema requirements.

Real-world Applications of NoSQL

Advantages and Disadvantages of NoSQL Databases

Advantages of NoSQL Databases

• High Performance and Low Resource Requirements: NoSQL databases can operate efficiently on systems with modest resources, eliminating the need for large servers.

• Horizontal Scalability: These databases allow for horizontal scaling by adding nodes, which enhances performance without significant infrastructure changes.

• Handling Large Volumes of Data: They can store vast amounts of information without creating bottlenecks in system performance.

• Flexibility in Data Storage: NoSQL databases offer greater flexibility regarding the types of data that can be stored compared to relational models.

Disadvantages of NoSQL Databases

• Lack of Reliability Functions: Unlike relational databases, NoSQL lacks constraints such as referential integrity, which may lead to data inconsistency.

• Increased Complexity in Security Schemes: The absence of built-in reliability functions necessitates additional programming for security measures within applications using these databases.

• Compatibility Issues with Query Languages: Searching through collections may require more processing power and time, especially when dealing with large datasets.

Introduction to MongoDB

Getting Started with MongoDB

• Popular Choice Among NoSQL Databases: MongoDB is highlighted as one of the most widely used NoSQL databases today.

• Installation Options: Users can choose between Enterprise or Atlas versions; however, the Community Edition is recommended for practice due to its free availability despite some limitations.

• Downloading Community Edition: Instructions are provided for downloading the Community Edition from the official MongoDB website, ensuring a straightforward installation process similar to other Windows applications.

Documentation and Resources

• Accessing Documentation: The documentation URL (docs.google.com) provides essential guides on installation and initial console operations.