There may be the scenarios where the compound SELECT statements may have different count and data type of selected columns.
Walk up to her, discretely check if there is a ring on that finger, and if she's availalble, make your move.
For number columns, zero can also be substituted to match the type of the columns selected in the query.
In the below query, the data type of employee name (varchar2) and location id (number) do not match.
Essentially,it removes duplicates from the results i.e.
only one row will be listed for each duplicated result.
The SET operators available in Oracle 11g are UNION, UNION ALL, INTERSECT,and MINUS.