A relational database is a database consisting of relation variables (which are also called *relvars*, *R-tables* or just *tables*). The definition, manipulation and integrity rules of relational databases are based on relational operations equivalent to or similar to the Relational Algebra and Calculus. Relational database principles are the basis of a substantial part of data management theory and practice.

Unified Modeling Language, an object-oriented modeling and specification language used in software engineering. For questions about user-mode Linux, use the [user-mode-linux] tag.

This tag is for programming questions about DevOps ("development" and "operations"), which is a software development method that stresses communication, collaboration, integration, automation, and measurement of cooperation between software developers and other IT professionals. Non-programming related questions should be asked on the DevOps Stack Exchange site.

A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use.

MySQL Workbench is a visual database design tool that is developed by MySQL. It is the successor application of the DBDesigner4 project.

Questions related to interacting programmatically with Google Calendar calendars and events. A language tag should also be included, e.g. [google-apps-script]. Questions about general use of Google Apps should be posted on Web Applications Stack Exchange.

GitLab CI is a continuous integration server from GitLab.

MPI is the Message Passing Interface, a library for distributed memory parallel programming and the de facto standard method for using distributed memory clusters for high-performance technical computing. Questions about using MPI for parallel programming go under this tag; questions on, eg, installation problems with MPI implementations are best tagged with the appropriate implementation-specific tag, eg MPICH or OpenMPI.

Amazon API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs at any scale.

Passport.js is authentication middleware for Node.js. Extremely flexible and modular, Passport can be unobtrusively dropped into any Express-based web application. A comprehensive set of strategies support authentication using a username and password, Facebook, Twitter and more.

The terms overloading and overloaded may refer to: - Constructor and method overloading, a type of polymorphism where different functions with the same name are invoked based on the data types of the parameters passed - Operator overloading, a form of functional or method overloading where the action being overloaded is an operator, such as + or -