This is a bug in Oracle 12.1. When you have a table in one schema (Schema1) with a sequence on some column and you want to insert in that table from another schema (Schema2), error message “ORA-00942: table or view does not exist” is displayed. This happens although you have privileges to select, insert, update or delete on the table in Schema1. To fix that, you need to grant SELECT on the sequence too. Hope Oracle find a way to display more suitable error message in such cases.
Table Event in Schema1 :
GRANT SELECT,INSERT,UPDATE,DELETE ON Event TO Schema2; GRANT SELECT ON Event_Id_SEQ TO Schema2;