Traditional Culture Encyclopedia - Traditional customs - What are the traditional set operations in relational algebra?
What are the traditional set operations in relational algebra?
Common set operations:
Power set p ()
Quotient set q ()
Empty set?
Complement set (difference set)
cross
And∨
Ring sum ⅶ
Ring products?
In relational algebra, it is mainly
True inclusion, unreal inclusion, inclusion and non-inclusion.
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