Translating SQL Queries into Relational Algebra
The initial plan
Example
Initial plan:
sort(
project(
select(
product(member f,
product(routing r, message m)),
and(f.member_id = r.to_member_id,
r.message_id = m.message_id,
extract(day from f.birth_date) = extract(day from m.message_date),
extract(month from f.birth_date) = extract(month from m.message_date))),
[f.name]),
[f.name])
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