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DECLARE @Codes VARCHAR(8000)
SELECT @Codes = COALESCE(@Codes + ', ': '') + tdefSymptomCode.SymptomCodeNumber
FROM RMA INNER JOIN
trelRMA_SymptomCode ON RMA.IdRMA = trelRMA_SymptomCode.fiRMA INNER JOIN
tdefSymptomCode ON trelRMA_SymptomCode.fiSymptomCode = tdefSymptomCode.idSymptomCode
where idRMA=2
order by SymptomCodeNumber
return @Codes