MS Access: Inner Joins vs. Outer Joins

[NoLimit]

When is it appropriate to use either kind of joins? I thought I understood it, but I got some answers wrong on a quiz because I used the wrong type of join when writing the query.

[vass0922]

Inner Join: When you want the fields from BOTH tables to match.

For instance in a classroom to student relationship. You'd only want students to appear when they ARE assigned to a classroom

On the other hand, an OUTER JOIN (Either LEFT or RIGHT) will show you ALL rows from ONE table, and ONLY the rows that match from the 2nd table.

So using the same example, you could desire a query that shows ALL students, but show classroom information about students who ARE assigned to a class

There is also a FULL OUTER JOIN but dont' think Access has those (access sucks lol )


That help or hurt?

[NoLimit]

Thanks for those examples. I sort of get it now.

[vass0922]

If you're still unclear on something let us know

[NoLimit]

I think I get it now. When you join two tables using an outer join, the field you're joining from table a doesn't have to have a match or value in table b in order to be displayed. Whereas with an inner join, it will only display fields that equal whatever was mentioned in the inner join. Does that sound right?

[vass0922]

Correct