Following is the color coding for the connection arrows and what they indicate:
A green arrow indicates that the mapping is supported without any warnings or errors. This mapping will not cause a data issue at the Runtime, and you can deploy the transformation to the Administrative Service.
An amber arrow specifies a warning message. The warning message appears in the Alert List view. It indicates that the mapping violates one or more transformation rules or conflicts with the supported data types. This mapping may or may not cause a data issue at the Runtime, it depends on the actual data being transformed. You can still deploy the transformation to the Administrative Service.
A red arrow indicates that there is an error. The error message appears in the Alert List view. The mapping violates one or more transformation rules or conflicts with the supported data types. In this case, you cannot deploy the transformation to the Administrative Service.
For more information about the supported data types and transformation rules, refer to Supported and Unsupported Mappings between Data Types and Transformation Rules, Errors, and Warnings.