Diagnosis
If field entries are used for the selection of another field, the fieldsshould be compatible in type. In this case the mapped fields are notcompatible.
This is only a warning because selects on entries of fields ofnon-compatible type cannot be principially forbidden. It depends on thesituation (i.e. the field entries) whether the mapping returns thecorrect results.
This warning is issued if

• the data types of the fields do not match (i.e. if you match a
character-type field to a numeric field, etc.),

• the length of the original field exceeds the one of the mapped field
(because in this case entries may be truncated).
No warning is issued if the field is shorter than the compare fieldbecause technically there is no problem to select with a shorter entryin a longer field.

Procedure
Check whether the mapping makes sense. See the technical information forthe table and field information.
In case of doubts check the Subscription Agent log on the most detailedlog level to see whether the expected results are returned.