All Oracle Error Codes
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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: online index rebuilds

Mark W. Farnham


You mean other than having to do an at best order n log n operation to create the index instead of reading the index in order so the order of the operation is merely n, and the overhead of absorbing dynamic changes to the table and resultant changes into the index being built?
As to the "WHY?" question, I'm not sure, but my guess would be that they believed the process flow of managing the changes while the new indexes was being built were more reliable that way.
Circa May 1991 the level of difficulty of getting the code provably correct to read the existing index to create the new index without locks was referred to by a guy who thought he might have to write it as "Jesus code," meaning no disrespect, but the notion that it would require a divine being to get it right.
Some alternate psuedo code to read the index to build the new index while locking only handfulls of blocks worth of rows at a time must not have made the cut, or was lost in the shuffle.
Probably the advantage of the full table scan is getting a handle on which rows need fixup in the new index image from the read consistent read to fix it up to the current committed image before you swap it in place.
I'm just guessing here.
 -----Original Message-----
From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org]On Behalf Of Roger Xu
Sent: Wednesday, January 25, 2006 3:05 PM
To: joseph@amalrajinc.com; Bobak, Mark; ORACLE-L
Cc: tanel.poder.003@mail.ee
Subject: online index rebuilds

Any other differences besides: 1) does not lock the table; 2) does a full table scan instead of full index scan; ?
-----Original Message-----
From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org]On Behalf Of Joseph Amalraj
Sent: Tuesday, January 24, 2006 9:48 AM
To: Bobak, Mark; joseph@amalrajinc.com; ORACLE-L
Subject: RE: ORA-01652: unable to extend temp segment

Had read the article, but I am interested as to why Oracle is doing a full table scan instead of full index scan for online index rebuilds.