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- In computer science, domain relational calculus (DRC) is a calculus that was introduced by Michel Lacroix and as a declarative database query language for the relational data model. In DRC, queries have the form: where each Xi is either a domain variable or constant, and denotes a DRC formula. The result of the query is the set of tuples X1 to Xn that make the DRC formula true. This language uses the same operators as tuple calculus,the logical connectives ∧ (and), ∨ (or) and ¬ (not). The existential quantifier (∃) and the universal quantifier (∀) can be used to bind the variables. Its computational expressiveness is equivalent to that of relational algebra. (en)
- El cálculo relacional basado en dominios (en inglés Domain relational calculus, DRC) es un cálculo propuesto por y como lenguaje de consulta declarativo para modelos relacionales de bases de datos. El cálculo tiene la misma expresividad que el álgebra relacional, y se implementa en el lenguaje SQL. (es)
- 在计算机科学中,域关系演算(DRC)是和为关系数据模型发明的的作为声明性数据库查询语言。 在 DRC 中,“查询”有如下形式: 这里的 Xi 要么是一个域变量要么是一个常量,而 p 指示一个 DRC “公式”。 查询的结果为使得这个 DRC 为真的元组 Xi 到 Xn 的集合。 域关系演算可以使用量词,同时使用与、或、非(以及蕴含算符);尽管如此,域关系演算的表达能力同非递归的Datalog程序是一样的 ,也等价于关系代数。 (zh)
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- El cálculo relacional basado en dominios (en inglés Domain relational calculus, DRC) es un cálculo propuesto por y como lenguaje de consulta declarativo para modelos relacionales de bases de datos. El cálculo tiene la misma expresividad que el álgebra relacional, y se implementa en el lenguaje SQL. (es)
- 在计算机科学中,域关系演算(DRC)是和为关系数据模型发明的的作为声明性数据库查询语言。 在 DRC 中,“查询”有如下形式: 这里的 Xi 要么是一个域变量要么是一个常量,而 p 指示一个 DRC “公式”。 查询的结果为使得这个 DRC 为真的元组 Xi 到 Xn 的集合。 域关系演算可以使用量词,同时使用与、或、非(以及蕴含算符);尽管如此,域关系演算的表达能力同非递归的Datalog程序是一样的 ,也等价于关系代数。 (zh)
- In computer science, domain relational calculus (DRC) is a calculus that was introduced by Michel Lacroix and as a declarative database query language for the relational data model. In DRC, queries have the form: where each Xi is either a domain variable or constant, and denotes a DRC formula. The result of the query is the set of tuples X1 to Xn that make the DRC formula true. This language uses the same operators as tuple calculus,the logical connectives ∧ (and), ∨ (or) and ¬ (not). The existential quantifier (∃) and the universal quantifier (∀) can be used to bind the variables. (en)
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- Cálculo relacional basado en dominios (es)
- Domain relational calculus (en)
- 域关系演算 (zh)
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