Archives of the TeradataForum
Message Posted: Fri, 31 Jan 2003 @ 11:00:49 GMT
Dave is right, as ever, but at a higher level than the mechanics involved, the queries are different in the question that is being asked.
The first will preserve the 1:1, 1:many, many:1 or many:many relationship between the two tables. The size of the result set depends on this relationship.
The second compares table 1 values to a distinct list of values in table 2 via a subquery. This is a constraint check on table 1 rather than a join between relations. The answer set can only be as large (or smaller) as the number of rows in table 1.
|Copyright 2016 - All Rights Reserved|
|Last Modified: 28 Jun 2020|