Translating SQL Queries into Relational Algebra
The initial plan
Example
Query:
select f.name
from member f, routing r, message m
where f.member_id = r.to_member_id
and r.message_id = m.message_id
and extract(day from f.birth_date) = extract(day from m.message_date)
and extract(month from f.birth_date) = extract(month from m.message_date)
order by name
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