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

Re: Reducing sga_target in 10gR2 without getting ORA-00827

Michael Ray


Schultz, Charles wrote:
> We had significant problems with sga_target, enough that we finally
> turned it off. Apparently, in there are some issues with the
> algorithm that allocates/deallocates memory which can cause degradation.
> Our Support Analyst(s) referenced the following bugs:
> 4466399/4472338 (dup) (SR 5386579.993): SYSTEM WIDE HANG ON MMON WAITING
> 4507532 (SR 5256243.992): SGA_TARGET DOESN'T WORK AS EXPECTED
> Not sure if this is relevant for your situation, but wanted to offer it
> up just in case.

That's certainly not comforting is it. We are still now because
I didn't see anything in the patches so far that dealt with SGA issues.

You may have a good idea of going manual, because this instance doesn't
vary much in transaction type or level. Frankly, I wonder if I've
stumbled onto some mem leak with the combination of parameters I've got
(nothing exotic) except I set _KGL_LARGE_HEAP_WARNING_THRESHOLD to get
rid of most of the gazillions of notifications in the alert log.
"Memory Notification: Library Cache Object loaded into SGA
Heap size 2251K exceeds notification threshold (2048K)"
I set it to 16MB I think and I've harldly seen any since. In
Oracle has set it to 50MB.

Their note (330239.1) on the subject has this interesting statement though:
"The meaning is that the process is just spending a lot of time in
finding free memory extents during an allocate as the memory may be
heavily fragmented. Real memory messages should be ORA-403x when a real
memory allocation problem occurs."
I clearly have a real memory problem (4030) every few weeks so why is my
mem so fragmented? Going manual is sounding better all the time.

Is manual SGA sizing in 10g done the same way it is in 8i? I have no
experience with 9i. Maybe I should sit down and figure out what all my
values should be. Now where were all those books...?


Michael Ray
Topshot Systems LLC