SQL Aggregating Mixed Data

Question

I have a table that has 3 columns

1. STA (which is equivalent to X)
2. BL (which is equivalent to y)
3. Ultimate_Load (which has positive and negative values)

I want to aggregate column 3 by the maximum of absolute values, but display the actual (negative or positive) value.

your help is appreciated

Answer 1

I think this would work. You get de max absolute value of ultimate_load and then change it's sign depending on the sign of MAX(ultimate_load)+MIN(ultimate_load).

SELECT STA,BL, MAX(ABS(ULTIMATE_LOAD)) * case sign(MAX(ULTIMATE_LOAD)+min(ULTIMATE_LOAD)) when 0 then 1 when -1 then -1 else 1 end as maxvalue
     FROM TAB
    GROUP BY STA, BL