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Incompatible Field Mapping

Jan Bogaert

When setting up custom mappings, you sometimes might bump into the following message: Field X is not compatible with field Y.

Screen Shot 2020-07-07 at 13 33 48

TLDR; This means that because of a technical reason, PieSync is unable to map these two fields to each other.

In this article we'll run through the 5 reasons why this might happen:

1. The data types of the two selected fields does not match.

Example: You want to map a number field to a boolean (yes/no) field. There is no way PieSync can make a field mapping for that, because the boolean field will not accept a number, it only accepts "true" or "false". The otherway around as well. The number field will only accept numbers. As such the field mapping will be considered to be incompatible.

2. PieSync cannot map the two fields, because of technical limitations (e.g. drop-down fields, radio buttons, checkboxes, etc).

Example: You want to map a dropdown fields with a dropdown field. In both apps both fields have identical values. Still, PieSync says they are incompatible. This is because PieSync cannot sync dropdown fields through the field mappings.

3. Complex fields with multiple values can’t be synced in a custom mapping.

What we mean by a complex field with multiple values is a field such as emails, phones and addresses where one field can have house multiple value (and might have a labels to distinguish them). This is the case in apps like Google Contacts, iCloud Contacts, etc.

Example: Your are trying to map a field called 'Phones (Mobile)' to a Mobile Phone field. This will not work, because 'Phones (Mobile)' is a subfield of the 'Phones' field, which is likely already mapped in the default field mappings.

4. One or both fields are read-only

Certain contact fields in your applications are not allowed to be modified. Sometimes third party-apps are specifically barred from modifying the field, at other times, it's generally a field that can only be populated by the app itself. Below is an example of a field that can't be modified through a third-party app and therefore only syncs one-way (→).


Bear in mind that the general direction of the sync decides your syncing behaviour. When you have your connection configured as a one-way sync in the other way (←), the following message will pop up.

5. There might be an issue with the partner API that is preventing us from exposing this field properly.

If none of the aforementione reasons checks out, then this might be the root cause of the incompatible field mapping. You can always reach out to PieSync Support (support@piesync.com) to get more information

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