ORA-08177: can't serialize access for the transaction with oracle_FDW

Question

oracle_fdw from postgres was randomly throwing ORA-08177. Wanted to either do a retry or figure out what was happening.

Answer 1

https://github.com/laurenz/oracle_fdw Unfortunately Oracle's implementation of SERIALIZABLE is rather bad and causes serialization errors (ORA-08177) in unexpected situations Using READ COMMITTED transactions works around this problem, but there is a risk of inconsistencies. If you want to use it, check your execution plans if the foreign scan could be executed more than once.

alter server oracle options ( set isolation_level 'read_committed');