Lookup Vs Join

[ghostraider]

I have three tables A,B,C coming from sql server database. Tables have the following columns

TABLE A
Apply ID
Apply Desc
Apply DOB
User ID

TABLE B
User ID
UserName

TABLE C
User ID
City Zip


I have to first map USER ID from Table A with Table B and then map Table C to get an output similar to below.

Output
ApplyID
ApplyDesc
UserID
City
Zip

So instead of using the hashed file to lookup i did a join on the three tables
in sql server itself i.e. instead of looking up with A with B and then B with C
i wrote a join for the three tables.

Select A.column,B.column,C.column from A
left outer join b on A.key=B.key
left outer join C on B.Key=C.Key

I used left outer join because i do not want to use the Not(ReferenceLink.NotFound) if i did a lookup. So could you guys tell me if the join yields different results to that of the lookup.

[ray.wurlod]

It would depend upon how you implemented the lookups, information that you have chosen not to provide. It is possible to achieve the same results with lookup as with join, provided that certain conditions are met.