ERRCODE_T_R_DEADLOCK_DETECTED

The error code is used in two places:
ereport(ERROR,        (errcode(ERRCODE_T_R_DEADLOCK_DETECTED),         errmsg("canceling statement due to conflict with
recovery"),  errdetail("User transaction caused buffer deadlock with recovery.")));
 
ereport(ERROR,        (errcode(ERRCODE_T_R_DEADLOCK_DETECTED),         errmsg("deadlock detected"),
errdetail_internal("%s",clientbuf.data),         errdetail_log("%s", logbuf.data),         errhint("See server log for
querydetails.")));
 

The latter is a normal deadlock and can be obseved by stats because
pgstat_report_deadlock() is called.

The former is using the same error code but the meaning is pretty
different and users might be confused IMO.

I am not sure sharing the same error code is the best idea here.

Best regards,
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese:http://www.sraoss.co.jp