RDBMS / SQL中的“关系”与“关系”？ [英] “Relation” versus “relationship” in RDBMS/SQL?

问题描述

来自问题关系与关系

RDBMS（或数据库理论）中关系与关系的定义是什么？

What are definitions of "relation" vs. "relationship" in RDBMS (or database theory)?

更新：

我对我的问题发表意见感到有些困惑：

Update:
I was somewhat perplexed by comment to my question:

关系是表的同义词，因此
在
计算机中存储的模式的
条款中具有非常精确的含义。

"relation is a synonym for table, and thus has a very precise meaning in terms of the schema stored in the computer"

Update2：

如果我错误地回答了这个问题，就RDBMS而言，写道关系是单向方向奇异连接依赖-link，

即从一个表到另一个表，而关系在一个方向上（从一个表到另一个表）暗示（不一定明确）多个链接连接？

Update2:
Had I answered incorrectly that question , in terms of RDBMS, having written that relation is one-side direction singular connection-dependence-link,
i.e. from one table to another while relationship implies (not necessarily explicitly) more than one link connection in one direction (from one table to another)?

推荐答案

RELATION是一组域的笛卡儿乘积的子集（ http://mathworld.wolfram.com/Relation.html ）。在日常术语中，关系（或更具体地说是关系变量）是大多数人称为表的数据结构（尽管SQL中的表不一定是关系）。

A RELATION is a subset of the cartesian product of a set of domains (http://mathworld.wolfram.com/Relation.html). In everyday terms a relation (or more specifically a relation variable) is the data structure that most people refer to as a table (although tables in SQL do not necessarily qualify as relations).

关系是关系数据库模型的基础。

Relations are the basis of the relational database model.

关系是不同的。关系是一种语义事物之间的关联。

Relationships are something different. A relationship is a semantic "association among things".

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