Is it possible to perform group by and sum operation in Mapper/Conditional snap?

Is it possible to perform sum of the values by grouping them on few fields in mapper/conditional snap in snaplogic.
Because with aggregate snap I’m losing all input fields and keeping copy snap is taking more time to execute.

Hi @nirupama,

There’s a group by functionality on the Aggregate snap that will allow you to have the input data in a group after you’re done with your calculations (Aggregation).

Another option is to use a Group by N snap, with 0 in group size which will add all incoming objects to one array. After that, you’ll need to add a Mapper snap with the following expression:

$array.reduce((acc, curr)=> acc + curr, 0)

You probably going to need to amend the expression per your needs. For example if you have an array of objects, and you need to calculate a specific field (ex. “Age”) the expression will look something like this:

$array.reduce((acc,curr)=> acc + curr.Age,0)


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Hi @bojanvelevski ,

Thanks you. I tried with group by N(It does batching randomly), but I want to group them based on 3 fields say $A,$B,$C and then I want to do SUM on other field $D.Is there any such functionalities available in snaplogic using mapper?

Same thing applies to your use case, just the grouping is a little bit different and you’ll have to use Group by Fields

@bojanvelevski I was trying with this approach, but getting below error.

expression using : $.reduce((acc,curr)=> acc + curr.INSTALLCUQTY,0)
Also, getting ‘null’ as output for sum.

Does it mean that your input is plain array literal and not an object array?


The error you’re receiving is telling you that the instance of “curr” - current is a BigDecimal. Can you provide a sample payload here?