How many rows may be retrieved by the select statement in the following SQL code samples?

1. count() Returns the number of rows found

2. having keyword should always follow the group by

3. A result set based on a query with a proper join condition is called a cartesian product

4. distinct requires an additional sorting step using a worktable

5. subquery always return single column of data

6. once you create a column and declare its datatype, you cannot change that datatype without dropping and recreating the table.


No comments: