The person id field within OMOP v4 is a numeric field. We have many data sources where the patient id is an alphanumeric field. As of now we are generating a person id for each source patient id. However, a challenge we have is linking patients with newer refreshes of the data. As of now the patient id can be stored in person source value but it becomes challenging to use this to link with new data refreshes. Is there a way that the person id field can hold alphanumeric values? Is there a way for us to change the data type of the person id? This would greatly help with our challenges.