Tag Info

I am somewhat aware of the correspondence between (tuple and domain) relational calculus, relational algebra, and SQL. To the best of my understanding, one should be able to automatically convert a ...

Let me concentrate, as you asked, on section $(\exists d)(\exists t)(\cdots)$. In case when one part of conjuction is "not depend" on letter under existence quantifier, holds $$(\exists d)(A ...

From Wikipedia: A tuple is of the form $T=(D,R,h)$ where $D$ is the domain, $R$ is a set of relation names, and $h$ is a mapping that associates a column name to each relation in $R$. To represent a ...

where Eid field is empty. What do you mean by "empty"? Perhaps you mean 'null'? What words exactly does your "solution manual" use? "empty" or "null"? If the Eid ...

Something like { c.name | ... } is shorthand for something like {z : (name) | (∃c) (z.name = c.name ^ ...) }. As described ...