Please note that after detaching a dSource (through the GUI or CLI) you can only reattach it through the CLI.
ssh delphix_admin@SYSTEM
delphix > database
delphix database > ls
delphix database > select "dexample"
delphix database "dexample" > attachSource
delphix database "dexample" attachSource *> set source.name=dexamplePrimary
delphix database "dexample" attachSource *> set source.config=example2
delphix database "dexample" attachSource *> set environmentUser=myuser
delphix database "dexample" attachSource *> set dbUser=orauser
delphix database "dexample" attachSource *> set dbCredentials.password=orauserpassword
delphix database "dexample" attachSource *> commit