Is inner join the same as equi-join?

Question

Can you tell me if inner join and equi-join are the same or not ?

Answer 1

Simply put: an equi-join is a possible type of inner-joins

For a more in-depth explanation:

An inner-join is a join that returns only rows from joined tables where a certain condition is met. This condition may be of equality, which means we would have an equi-join; if the condition is not that of equality - which may be a non-equality, greater than, lesser than, between, etc. - we have a nonequi-join, called more precisely theta-join.

If we do not want such conditions to be necessarily met, we can have outer joins (all rows from all tables returned), left join (all rows from left table returned, only matching for right table), right join (all rows from right table returned, only matching for left table).