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A check constraint is a type of integrity constraint in SQL which specifies a requirement that must be met by each row in a database table. The constraint must be a predicate . It can refer to a single column, or multiple columns of the table.
Database Workbench started out as a developer tool specifically for InterBase, "InterBase Workbench", initially modeled after the SQL Navigator tool for Oracle Database by Quest Software. [ 4 ] [ 5 ] During its early years, InterBase became open-source for a short while, and soon after Firebird was created as a fork from the InterBase code base .
On April 5, 2018, the MySQL Workbench Team announced [28] the first public release of version 8.0.11 as a Release Candidate (RC) together with MySQL Community Server 8.0.11. The first General Availability (GA) release appeared on July 27, 2018 [ 29 ] again together with the server following the new policy for aligning version numbers across ...
In database systems, consistency (or correctness) refers to the requirement that any given database transaction must change affected data only in allowed ways. Any data written to the database must be valid according to all defined rules, including constraints, cascades, triggers, and any combination thereof. This does not guarantee correctness ...
MySQL (/ ˌ m aɪ ˌ ɛ s ˌ k juː ˈ ɛ l /) [6] is an open-source relational database management system (RDBMS). [6] [7] Its name is a combination of "My", the name of co-founder Michael Widenius's daughter My, [1] and "SQL", the acronym for Structured Query Language.
In an Oracle database, a change vector consists of a single change to a single data block. A change vector is the smallest unit of change recorded in a redo log (in its turn, a redo log comprises files in a proprietary format which logs a history of all changes made to the database).
A data control language (DCL) is a syntax similar to a computer programming language used to control access to data stored in a database (authorization).In particular, it is a component of Structured Query Language (SQL).
A transition constraint is a way of enforcing that the data does not enter an impossible state because of a previous state. For example, it should not be possible for a person to change from being "married" to being "single, never married". The only valid states after "married" might be "divorced", "widowed", or "deceased".