Flatfiles

Flatfiles are simple data storage formats that consist of plain text files in which records are stored sequentially without the overhead of a relational database management system. Each line typically represents a single record, and fields within a record are separated by delimiters such as commas (CSV), tabs (TSV), or other characters like pipes. Because they lack indexes, schemas, and transaction support, flatfiles are easy to create, read, and edit with basic tools, making them popular for configuration data, log files, and lightweight data exchange.

The primary advantages of flatfiles include minimal hardware requirements, human readability, and straightforward portability across operating systems. They are useful for small‑scale applications, prototyping, or situations where the data volume does not justify the complexity of a full database. Additionally, flatfiles can serve as interchange formats between disparate systems, facilitating import/export operations.

However, the simplicity of flatfiles introduces limitations. Searching and updating specific records may require scanning the entire file, leading to poor performance on large datasets. The absence of built-in concurrency control can cause data corruption when multiple processes write simultaneously. Flatfiles also provide no enforcement of data types or integrity constraints, placing the burden of validation on application code.

Common usages include configuration files (INI, JSON, YAML), log files, CSV datasets for statistical analysis, and data migration scripts. When scalability, security, or complex queries are required, developers often transition to relational or NoSQL databases that offer indexing, transactional guarantees, and richer query capabilities.