How to quickly enable constraint with ENABLE VALIDATE for a big table in 12c
Posted on 2016-10-24
Have a relatively big table T1 with 200 million rows. Its FK points to a table T2 with 10 millions. In 11gR2, it took 3 hours to enable the FK constraint, but in 12c, it takes days to do it. T1 and T2 in the 2 environments were created with the same setting.
Can any gurus shed some light on it? How to speed up the valid process in 12c? Thanks in advance.