| OHDSI Home | Forums | Wiki | Github |
Hi guys,
I’m working on the design of the ETL process. In my source data, there is a unique identifier for each visit record. In this case, do I need to generate a new visit_occurrance_id? I’m worried about this because I did not find a field in visit_occurrance to store the source visit id. I’m considering the visit_source_value, but in the documentation of CDM v6, it says:
Thank you.
If you visit_id from the source is an integer and it is non-sensitive you could definitely use it to populate visit_occurrence_id. If visit_id is not an integer and you want to preserve it for local use, you can always create an extra column in the table with the prefix _
Hi, @jposada . Thank you again for your help. You mentioned: “you can create an extra column in the table with the prefix _”. I was not aware that we are able to do this. Can you share some related tutorials or documentation related to this?
No tutorial, @Dawei_Zhou. Just ordinary database behavior. Adding any fields, with an underscore or without, does not change the behavior of the existing fields (other than eventually making the system slower). So, you can add any field you want. It won’t be useful for anybody else but you, and the tools and network studies won’t know it even exists.
