>>I ran the two bottom selects and saved them to tables: T1 and T2. And the following now works! Thank you! This is a big
>>shift for someone who was firmly wedded to set relation, etc.
>>
>>

>>select  ;
>>NVL(T1.RatingMax,0) + NVL(T2.RatingMAX,0) as SumMAXs, ;
>>NVL(T1.yyMMddhh, T2.yyMMddhh)  AS yyMMddhh	;
>>FROM;
>>T1	 ;
>>FULL JOIN  ;
>>T2	;
>>ON T1.yymmddhh = T2.yymmddhh
>>

>>
>>Is there a way to make the output look like this, that is to include the columns for the corresponding maxes for T1 and T2.
>>I tried adding in fields to my two bottom selects, but when I try, it isn't working, maybe because there is a MAX in there
>>and also a GROUP BY?
>>
>>

>>TheDate  MaxT1  MaxT2  SumMAXs
>>201301    2.5       1.3        3.8
>>

>>
>>this produces an error, for example
>>
>>

														
>>select  ;
>>mRating			,;  && tried to add in the mRating field, so it would be in the result
>>MAX(mRating) 	as RatingMAX					,;
>>substr(CAST(mIndex as C(14)),1,6) as yyMMddhh	;
>>from tab1 					;
>>GROUP BY 3  && tried to change this to 3 since want to group on 3rd column which is yyMMdd?					
>>

>>
>>This works:
>>
>>

>>select  ;
>>MAX(mRating) 	as RatingMAX					,;
>>substr(CAST(mIndex as C(14)),1,6) as yyMMddhh	;
>>from tab1 					;
>>GROUP BY 2
>>

>
>Your last question doesn't have much sense since you're selecting maximum rating. Which rating do you want to see in addition to that?
>
>Do you want to see the date and hour and minute when that max rating was achieved? This would make more sense but the query will be a bit more complex.
>
>I would go with the composed column solution for this case, e.g.
>

>select max(mRating) as MaxRating,
>RIGHT(max(cast(mRating as C(20)) + CAST(mIndex as C(14))),14) as WhenMaxRatingHappened,
>LEFT(CAST(mIndex as C(14)),6) AS YearMonth
>FROM Tab1
>GROUP BY 3

Thank you for the above! The FULL JOIN produces this output:

SumMax's  YYMM
20.5             201301
19.2             201302

For a report, it would really help to have the option of including the MAX ratings for each table, such as:

MaxT1  Max T2  SumMax's  YYMM
5.6       4.1     9.7      201301
2.4       1.3     3.7      201302

And here it is:

select  ;
t1.RatingMax	as t1MAX,;
t2.RatingMax	as t2MAX,;
NVL(T1.RatingMax,0) + NVL(T2.RatingMAX,0) as SumMAXs, ;
NVL(T1.yyMMddhh, T2.yyMMddhh)  AS yyMMddhh	;
FROM;
T1	 ;
FULL JOIN  ;
T2	;
ON T1.yymmddhh = T2.yymmddhh