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Field Mapping using functions
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Target
Note:
When adding the mongodb primary key _id in the mapping as a target, when running the pipeline, if the _id does not yet exist, mongodb will create new documents, if they exist, mongodb will not create new documents but those existing in mongodb with the same _id will be updated instead on whatever the incoming data is. This is the known behavior for mongodb and EazyDI was designed not to prevent or hinder what the behavior of mongodb is so users will have full control on how to use it.
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