sas inner join vs left join with same data set

[Sasadomo]

I am wondering if there's any difference between inner join and left join if I am self merging. 

Say I use the DOSING data set in the following document

http://www2.sas.com/proceedings/sugi25/25/cc/25p109.pdf

And I condition it on patient ID = patient ID, Then using inner join and left join would create the same result right?

[SASKiwi]

Why not try it and prove it to yourself?

[RW9 · Accepted solution]

There are plenty of resources that graphically show what joins do.

[Kurt_Bremser]

Maxim 4.