Adrian McMenamin

Basic symbols of relational algebra

Apologies in advance but this blog might start to look like online revision notes (and a LaTeX scratchpad) for the next six weeks.

Projection

\Pi_{field1, field2, \ldots fieldn} ( D )

Selection

\sigma_{field1=condition \wedge field2=condition}(D)

Rename

\rho ( E ( \bar F ) , D )

Conditional Join

D \Join _{field1 = condition} E

Natural Join

D \Join E

(Page 100 onwards of Database Management Systems, Third Edition)

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