How to disable system trigger when database is not open

Dear All,

Today I learn something new from OTN.

there is one question posted about trigger error ORA-04098,

alter database open resetlogs throws error like

ORA-04098: trigger 'APPS।LOGON_TRGR' is invalid and failed re-validation

Now database is in "mount" stage and we can't disable,drop or fix the trigger error without OPEN the database।

so there is one UnderScore parameter called ""_system_trig_enabled"" ।

This parameter we can set in SPFILE/PFILE "_system_trig_enabled=FALSE" and startup the database।