An error in my T-SQL
Column XXX is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
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http://sqlzoo.net/howto/source/z.dir/err979/sqlserver
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.
SELECT name, region, MAX(population)
FROM bbc
GROUP BY region
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
Specific to SQL Server
