All Oracle Error Codes
Oracle DBA Forum

Frequent Oracle Errors

TNS:could not resolve the connect identifier specified
Backtrace message unwound by exceptions
invalid identifier
PL/SQL compilation error
internal error
missing expression
table or view does not exist
end-of-file on communication channel
TNS:listener unknown in connect descriptor
insufficient privileges
PL/SQL: numeric or value error string
TNS:protocol adapter error
ORACLE not available
target host or object does not exist
invalid number
unable to allocate string bytes of shared memory
resource busy and acquire with NOWAIT specified
error occurred at recursive SQL level string
ORACLE initialization or shutdown in progress
archiver error. Connect internal only, until freed
snapshot too old
unable to extend temp segment by string in tablespace
Credential retrieval failed
missing or invalid option
invalid username/password; logon denied
unable to create INITIAL extent for segment
out of process memory when trying to allocate string bytes
shared memory realm does not exist
cannot insert NULL
TNS:unable to connect to destination
remote database not found ora-02019
exception encountered: core dump
inconsistent datatypes
no data found
TNS:operation timed out
PL/SQL: could not find program
existing state of packages has been discarded
maximum number of processes exceeded
error signaled in parallel query server
ORACLE instance terminated. Disconnection forced
TNS:packet writer failure
see ORA-12699
missing right parenthesis
name is already used by an existing object
cannot identify/lock data file
invalid file operation
quoted string not properly terminated

Determining License High Water Mark without shutdown

Paul Vincent


Recently we needed to increase the PROCESSES parameter due to a major increase in system usage. Rather than wait for a spate of reported ORA-00020 messages, I'm keeping an eye on the "License High Water Mark" entry in the alert log each time the instance is shut down, so I can increase PROCESSES again if the demand starts to approach the limit again. The problem is, this message only appears at shutdown, which isn't very helpful. What I'd like to be able to do is, at any time, see what the current High Water Mark is. Now, honest folks, I've RTFM'ed for all I'm worth, but can't find the relevant system view that contains this information. I should emphasise that I'm not looking for the current number of sessions at a moment in time, I'm looking for the high water mark figure since the last time the instance was started up.
Can anyone point me in the right direction, please, or let me know if the information *can't* be determined other than at shutdown?
Paul Vincent
UCE Birmingham