In my applications that are already running for long time
and would be hard to modify, I am considering to use the code below

A random number would be added to the code to prevent duplications

Do you think 1 in 10,000 is good a range to prevent duplications ?

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add_code = Int(10000*Rand())

dimension lctemp[1]
select max(ap.id2) from ap ;
into array lctemp
lcTemp[1] = nvl(lcTemp[1],0)+1 + add_code
replace ap.id2 with lctemp

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