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ORA-18 ORA-604 Making New Connections to Database (Doc ID 1036728.6)

Last updated on FEBRUARY 02, 2022

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.


 You receive the following errors when trying to make new connections:

ORA-00604: error occurred at recursive SQL level 1
Cause: An error occurred while processing a recursive SQL statement.
               (a statement applying to internal dictionary tables).
Action: If the situation described in the next message on the stack can be corrected, do so; otherwise, contact customer support.


ORA-00018: maximum number of sessions exceeded
Cause: An operation requested a resource that was unavailable.
               The maximum number of sessions is specified by the initialization parameter SESSIONS.
               When this maximum is reached, no more requests are processed.
Action: Try the operation again in a few minutes. If this message occurs often, shut down Oracle, increase the SESSIONS parameter in the initialization parameter file, and restart Oracle.

NOTE: No new connections are permitted to the database.

Selecting count(*) from V$SESSION returns a value that is less than the current setting of the SESSIONS parameter which is either derived (default) or specifically set in the "init.ora".




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