SQL MAX() equivalent in ABL?

[D.Cook]

I think I've had to solve this problem in the past but can't remember how...

If you're familiar with SQL, you'll know you can do something like SELECT MAX(a_column) FROM a_table, which will find the highest value of a numerical column in the table.

Is there a quick way to do this in ABL, or do I need to loop through every value, keeping a temp variable for the highest value?

 

[JamesBowen]

Have a look at Aggregate phrase in the Manual

FOR EACH customer NO-LOCK:
    DISPLAY customer.customer_ID customer.paid(MAXIMUM).
END.

 

[D.Cook]

Thanks for the suggestion Cecil. I came up with this, which will put the value into a variable.

def var iMax as int.

for each customer fields(paid):
    accumulate customer.paid (maximum).
end.

iMax = (accum maximum customer.paid).

But for this case I ended up with an index on the numerical field, and a FIND LAST using the index, which should give me the record containing the highest number.

 

[jdpjamesp]

Surely it would be better to have the index defined as DESC and then find first?

 

[TomBascom]

Why is that?

 

[jdpjamesp]

Just a thought... but then I thought again.