How to avoid MNI

Question

Hi All, 
 Is is best practice to use MNI's in appian , if we need to avoid this could suggest me the ways to so ? 
 Thanks, 
 Bhargavi

Dave Lewis · Answer

In general, MNI isn't a BAD practice or something to AVOID or anything like that. 
 It's simply just SLOW and limited to only 1000 iterations. 
 Looping can be a good alternative at times, if it makes more sense for your process model. In general I would use looping when I expect several operations, not just one, to be done on each item in sequence. If it's something where I need to run script task A, script task B, and write to database node C, and then run all three on the next record, and the next after that. If it's impossible to do those steps out of order and get the correct result, I would loop. Looping also has the same limitation of 1000 iterations. It's also just as SLOW if not a little slower. 
 a!forEach has 2 advantages. It's FAST, maybe even several hundred times as fast. It's limited to 1,000,000 iterations! It has 3 severe limitations though. First, it can only do expression rules. If appain hasn't ported the smart service node you need to an expression rule yet, you can't a!forEach a solution. Second, you have to code all the logic; you can't model it. If it needs a looping or branching structure to it's logic, one that you could easily model in the process modeler, but one that you can't wrap your head around making a rule for, it's going to be painful to make an a!forEach for the solution. Third, you can't a!forEach a subprocess. a!startProcess is restricted from working in any looping functions. 
 If you got an MNI working and the performance isn't a problem, congratulations! Don't do anything. 
 If you got an MNI working and the performance is a problem, try to determine if it would be worth taking a crack at replacing it with an a!forEach, or just optimizing the MNI or loop. If both seem about equally feasible, go with the a!forEach.

ajinkyab277 · Answer

back in portal days MNI was good weapon to deal with the looping logic . rather than implementing the looping logic with xor , increament count script task. But after introduction of apply function (and then replaced by for each) MNI has minimul usage. below are some usage of MNI 
1. If you want to assign the user input task in everyone of group (one on one user task mapping ) 
2. if you want to call the sub process node for each item in list

Mike Schmitt · Answer

No, I wouldn't go with an XOR loop - this is a reasonable case for MNI usage, as long as you don't end up with problems storing your generated documents into a PV.

How to avoid MNI

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