Oracle Not A Group By Expresion Error

Problem

When using a GROUP BY clause every field in the SELECT list must be either:

• One of the GROUP BY terms - in this case region
• An aggregate function - for example SUM or COUNT
• An expression based on the above

In the example the field name may not be used on the SELECT line.

In a group by line each region shows up only once - however in a typical region such as Africa there are several different name values. WHich one should SQL pick?

Solutions

• Remove the offending field from the SELECT line
• Add the field to the GROUP BY clause
• Aggregate the offending field