-- Run: a data set is loaded from system A to system B.
-- Step: a part of a run at the lowest grain from system A (most likely a table). Child of Run.
-- Log: keeps track of every time a step was executed and it's exit value.

-- Run
RunID (primary key)
system A
system B

-- Step
RunID (foreign key to Run)
StepID (primary key)
Type of load (SQL, ETL tool, etc)
Code to load (SQL statement, command line call, etc)

-- Log
LogID (primary key)
RunID (foreign key to Run)
StepID (foreign key to Step)
Start datetime
End datetime
Status (Error, Processed, Rollback)
Message (In case of error or rollback)