What's the created Date-time for Table row in

问题:

Yesterday my friend -BI Specialist - explained me an oracle problem :
there's an oracle database that contain huge amount of data but they don't make column for each table that store Created datetime for each row.
So in this case How can he get Created datetime (timestamp) for each row ?

回答1:

Every row has its own System Change Number (SCN). This is identifying precisely a moment in the database.

First find out the SCN and based on it use SCN_TO_TIMESTAMP to get the time-stamp:

SELECT 
  SCN_TO_TIMESTAMP(ora_rowscn),
  MyTable.*
FROM 
  MyTable