小知识：使用errorstack定位特定问题

有客户遇到ORA-2289的报错，同事协助去现场排查，我帮着远程共同check下。
客户只是应用端报出的错误，为了进一步定位，服务端需要开errorstack协助定位具体问题。
下面就以这个ORA-2289为例，示范下errorstack的使用方法。

--开启errorstack alter system set events '2289 trace name errorstack level 3';  --关闭errorstack alter system set events '2289 trace name errorstack off'; 

开启errorstack期间，模拟一个会话发生了ORA-02289的报错：

[oracle@bogon trace]$ sqlplus / as sysdba  SQL*Plus: Release 19.0.0.0.0 - Production on Wed Apr 26 22:00:21 2023 Version 19.16.0.0.0  Copyright (c) 1982, 2022, Oracle.  All rights reserved.   Connected to: Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production Version 19.16.0.0.0  SQL> select s2.nextval from dual; select s2.nextval from dual        * ERROR at line 1: ORA-02289: sequence does not exist   SQL> exit 

在alert告警日志可以看到提示：

2023-04-26T22:00:27.300427+08:00 Errors in file /u01/app/oracle/diag/rdbms/demo/demo/trace/demo_ora_3435.trc: ORA-02289: sequence does not exist 

进而在trc文件中进一步查询具体报错的SQL信息等：

[oracle@bogon trace]$ vi demo_ora_3435.trc  ...    17 *** 2023-04-26T22:00:27.300081+08:00 (CDB$ROOT(1))    18 *** SESSION ID:(2548.56891) 2023-04-26T22:00:27.300150+08:00    19 *** CLIENT ID:() 2023-04-26T22:00:27.300158+08:00    20 *** SERVICE NAME:(SYS$USERS) 2023-04-26T22:00:27.300164+08:00    21 *** MODULE NAME:(sqlplus@bogon (TNS V1-V3)) 2023-04-26T22:00:27.300170+08:00    22 *** ACTION NAME:() 2023-04-26T22:00:27.300177+08:00    23 *** CLIENT DRIVER:(SQL*PLUS) 2023-04-26T22:00:27.300182+08:00    24 *** CONTAINER ID:(1) 2023-04-26T22:00:27.300189+08:00    25     26 dbkedDefDump(): Starting a non-incident diagnostic dump (flags=0x0, level=3, mask=0x0)    27 ----- Error Stack Dump -----    28 <error barrier> at 0x7ffed8393280 placed dbkda.c@298    29 ORA-02289: sequence does not exist    30 ----- Current SQL Statement for this session (sql_id=c6bu1kcbt5z3f) -----    31 select s2.nextval from dual    32     33 ----- Call Stack Trace -----    34 calling              call     entry                argument values in hex    35 location             type     point                (? means dubious value)    36 -------------------- -------- -------------------- ----------------------------    37 ksedst1()+95         call     kgdsdst()            7FFED83926E0 000000002 ... 

我这里模拟是直接查询了不存在的序列，但是报这个错误其实未必是数据库问题，可以在MOS多搜索下相关案例，也有程序配置问题导致的情况。