Post #398 2.66K Jan 18, 2023, 06:59 UTC #数据库最近在看SQL相关的资料,有几个比较偏门的Join操作不知道什么含义,比如EquiJoin、AntiJoin等,维基百科上关系代数这页的讲解就比较清晰:https://en.wikipedia.org/wiki/Relational_algebra Wikipedia Relational algebra In database theory, relational algebra is a theory that uses algebraic structures for modeling data and defining queries on it with well founded semantics. The theory was introduced by Edgar F. Codd.[1] 👍 11