Question

To tell oracle to create NULL ROWS for records that don't have a matching row, use an outer join operator, which looks like this (+). It's placed in the where clause immediately after the column name from the table that's missing the matching row. What operator is used to create NULL ROWS for records that don't have a matching row in Oracle?

1) Inner join
2) Left join
3) Right join
4) Full outer join

Answer 1

In Oracle, the outer join operator (+) creates NULL ROWS for records without a matching row, equivalent to a left or right join, depending on the side missing information.

Step-by-step explanation:

The operator used in Oracle to create NULL ROWS for records that don't have a matching row is an outer join operator. In particular, when you see the (+) symbol placed immediately after the column name in the WHERE clause, it signifies the use of Oracle's proprietary join syntax to indicate an outer join. This is equivalent to the left join or right join in standard SQL, depending on which side of the join the missing information is expected to come from. In contrast, an inner join would not generate NULL rows for non-matching records, and a full outer join would include all records from both tables, with NULLs for non-matching columns from either side.

The operator used to create NULL ROWS for records that don't have a matching row in Oracle is the Left join operator. This operator is represented by the symbol (+) and is placed in the WHERE clause immediately after the column name from the table that's missing the matching row. When using a Left join, all the records from the left table are returned, and any corresponding records from the right table are included if they exist. If there is no matching row, NULL values are returned for the right table's columns.