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SELECT t2.[index], t1.[type], t1.code, AVG([current]) avg_current, AVG([bpo]) avg_bpo, AVG([forecast]) avg_forecast

FROM table1 t1

INNER JOIN table2 t2 ON t2.code = t1.code

GROUP BY t2.[index], t1.[type], t1.code

ORDER BY t2.[index], t1.[type], t1.code;