| 释义 |
relational calculus
关系演算(式)
In relational database, a language in which a user specifies the set of results required from the manipulation of the data. Relational calculus provides a concise unambiguous mathematical notation for statements. Compare relational algebra.
关系数据库使用的一种语言，用户可以用来规定数据操作所需的一组结果。关系运算为语句提 供了简明无歧义的数学记号。
参阅relational algebra, relation。 |