databasemanagement

Database management is the administration of database systems to store, organize, secure, retrieve, and maintain data. It encompasses the use of database management systems (DBMS) and related tools, processes, and policies to ensure data availability, integrity, and security.

A DBMS provides a structured interface for creating, querying, updating, and administering databases. Data is stored in schemas and organized by data models, with metadata describing structure and constraints.

Data models include relational (tables, rows, columns), document, key-value, columnar, and graph. Most traditional systems are relational; others are used for non-relational workloads.

Core operations involve defining data structures, manipulating data (create, read, update, delete), and querying data using languages such as SQL or other query languages. Transaction support ensures atomicity, consistency, isolation, and durability (ACID).

Design and integrity focus on normalization to reduce redundancy, indexing to speed queries, constraints to enforce data integrity, and schema design to guide data relationships.

Concurrency and performance cover concurrency control, locking, multi-version concurrency control (MVCC), query optimization, and caching.

Security and recovery address authentication, authorization, encryption, auditing, backups, and disaster recovery planning.

Deployment and scalability discuss on-premises and cloud-based DBaaS options, replication for availability, and techniques like sharding and clustering to scale, along with routine maintenance tasks such as patching.

Roles and governance describe the responsibilities of a database administrator (DBA) who manages systems, and broader data governance policies that address data quality, privacy, and compliance.

Examples of widely used DBMS include Oracle, MySQL, PostgreSQL, Microsoft SQL Server, MongoDB, Cassandra, and Redis.