Jnnn processes execute jobs. To execute a job, the process creates a session to run the job. When a Jnnn process runs a job, the job is run in the same environment in which it was submitted and with the owner's default privileges. The owner must be explicitly granted the necessary object privileges for all objects referenced within the job definition.
When you force a job to run using the procedure DBMS_JOB.RUN, the job is run by your user process and with your default privileges only. You must be explicitly granted the necessary object privileges for all objects referenced within the job definition.
很有可能是权限问题
job并没有继承dba之类权限
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