A database cluster is a group of interconnected computers or servers that work together as a single system to manage and process database operations.

A database is an organized collection of structured data stored and accessed electronically.

Database design is the process of producing a detailed data model of a database system, involving conceptual, logical, and physical design phases.

An ER model is a conceptual data model that shows the relationships between different entities in a database.

SQL (Structured Query Language) is a programming language for managing and manipulating relational databases.

Normalization is the process of organizing data in a database to reduce redundancy and anomalies, following a set of normal forms.

1NF requires that each cell in a table contains a single value, with no repeating groups.

2NF requires that a table is in 1NF and all non-key attributes are fully dependent on the entire primary key.

3NF requires that a table is in 2NF and all non-key attributes are mutually independent (not dependent on other non-key attributes).

A transaction is a logical unit of work that must be completed entirely or not at all, following the ACID properties.

ACID stands for Atomicity, Consistency, Isolation, and Durability, which are the key properties of database transactions.

A primary key is a column or set of columns that uniquely identifies each row in a table.

A foreign key is a column or set of columns that refers to the primary key of another table, establishing a relationship between the tables.

A data model is an abstract representation of the data structures and relationships within a database system.

A conceptual data model is a high-level representation of the entities and relationships in a database, typically using an ER model.

A logical data model is a detailed representation of the database structure, including tables, columns, and relationships, often using a data definition language.

A physical data model is a low-level representation of the database structure, including file organization and indexes, specific to the database management system being used.

Data redundancy occurs when the same data is stored in multiple places within a database, leading to potential inconsistencies and inefficiencies.

An index is a data structure that improves the speed of data retrieval operations by creating a sorted representation of the data in a table or view.

A view is a virtual table that presents data from one or more tables in a specific format, without duplicating the data itself.

A stored procedure is a pre-compiled code block that can be executed to perform a specific task within a database system.

A trigger is a special type of stored procedure that is automatically executed when a specific event occurs, such as an INSERT, UPDATE, or DELETE operation.

Database security involves the measures and practices used to protect a database from unauthorized access, misuse, or data corruption.

A database backup is a copy of the data in a database that can be used to restore the database in case of data loss or corruption.

Database recovery is the process of restoring a database to a consistent state after a failure or error, using techniques such as transaction logs and backups.

A JOIN operation is used to combine rows from two or more tables based on a related column between them, such as an INNER JOIN, LEFT JOIN, RIGHT JOIN, or FULL OUTER JOIN.

A subquery is a query nested within another SQL query, often used to retrieve data and apply conditions based on the results of the inner query.

A database schema is a logical collection of database objects, such as tables, views, stored procedures, and functions, that are related to each other.

Database replication is the process of copying data from one database to another, often used for distributing data across different locations or for backup and recovery purposes.

A database partition is a way of dividing a large table or index into smaller, more manageable pieces, often based on specific criteria or ranges.

A data warehouse is a specialized database system designed for storing and analyzing large amounts of historical data from various sources, often used for business intelligence and decision support.

Data mining is the process of discovering patterns, trends, and relationships within large datasets stored in databases, using statistical and machine learning techniques.

A database constraint is a rule or restriction that defines the allowable data values or relationships in a database, helping to enforce data integrity and consistency.

Database denormalization is the process of intentionally introducing redundancy or non-normalized data structures to improve query performance or simplify data models, at the cost of increased storage requirements and potential data inconsistencies.

A database index is a data structure that improves the speed of data retrieval operations by creating a sorted representation of the data in a table or view.

A database lock is a mechanism used to control concurrent access to shared resources, such as tables or rows, to prevent conflicts and maintain data integrity during read and write operations.

A database deadlock is a situation where two or more transactions are waiting indefinitely for one another to release resources, resulting in a stalemate that must be resolved by terminating one or more transactions.

A database trigger is a special type of stored procedure that is automatically executed when a specific event occurs, such as an INSERT, UPDATE, or DELETE operation, allowing for additional actions or validations to be performed.

A materialized view is a pre-computed and stored result set derived from a complex query, designed to improve query performance by reducing the need to recalculate the data on each query execution.

A database transaction log is a file or set of files that record all the changes made to a database, used for recovery purposes in case of system failures or to support features like replication and point-in-time recovery.

A database cursor is a control structure that allows for the retrieval and processing of result sets, one row at a time, enabling efficient memory management and processing of large data sets.

A database connection pool is a cache of pre-established database connections that can be reused by applications, reducing the overhead of creating and closing new connections for each request.

Database sharding is a technique used to horizontally partition and distribute large databases across multiple servers or instances, improving scalability and performance by allowing parallel processing and load balancing.

A database query optimizer is a component of a database management system that analyzes SQL queries and determines the most efficient execution plan for retrieving the requested data, considering factors like indexes, statistics, and available resources.

A database schema migration is the process of updating or modifying the structure of a database, such as adding, removing, or altering tables, columns, or constraints, while preserving the existing data and ensuring data integrity.

A database foreign data wrapper is a mechanism that allows a database management system to access and integrate data from external sources, such as flat files, Web services, or other database systems, as if they were local tables.

A database audit trail is a record of changes made to a database, including information about the user, operation, and timestamp, used for monitoring, compliance, and security purposes.

A primary key is a column or set of columns that uniquely identifies each row in a table and cannot contain null values, while a unique key ensures that the values in a column or set of columns are unique, but can contain null values.