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The relational database model is a fundamental concept in database management. It organizes data into one or more tables, also known as relations, where each table contains columns (attributes) and rows (tuples). Each row represents a distinct record, and each column represents a specific piece of information about that record. The key principle of the relational model is the use of keys to establish relationships between tables. Primary keys uniquely identify each row within a table, while foreign keys in one table reference the primary key of another table, thereby linking related data. This structure allows for efficient data storage, retrieval, and management. Data integrity is maintained through constraints, such as primary key uniqueness and referential integrity enforced by foreign keys. The relational model was first proposed by E.F. Codd in 1970 and has become the dominant model for database systems, powering countless applications worldwide. It supports a structured query language, most notably SQL (Structured Query Language), which is used to interact with and manipulate the data within these databases.