Calculate the total investment value in 2012 using two decimal places, ensuring that the same holder is not counted multiple times, utilizing three inner joins.
Use the provided holder, account, investment, and investment value records. Include qualifying 2012 records only, and prevent duplicate valuation records from inflating the result.
Output
- Return one row with
total_investment_value and qualifying_holders.
- Report the combined value to two decimal places and the number of unique holders represented.
- Return exactly one result row.
