如何找到同一列中两个日期之间的差异？

I have a table SO_STATUS that writes a record for each status change for a service order (we'll call the Service_Order_ID "Job_ID"). Job_ID references SERVICE_ORDER table. When the service order is initialized, a record is written for that status type of "open" (StatusType 2) which shows the datetime. Then another record is written in the status table for when it is "in progress" (StatusType 1). And also when the service order is "closed", another record written in the status table (StatusType 3). There are also other status types that may happen, but these are the most common. The data in the SO_STATUS table looks like this:I have a table SO_STATUS that writes a record f