ORA-00020, ORA-01304, ORA-27101 basic troubleshooting

ORA-00020, ORA-01304, ORA-27101 troubleshooting # ORA-00020 Problems
During fixed-point maintenance, the "Next" mode is used for installation of the database by Windows software. All configuration parameter values are default values. But because the number of billing endpoints of the specified point is large, the number of user processes that log on early in the morning exceeds the upper limit, will prompt "ORA-00020: exceeds the maximum number of processes (% s)", not a professional DBA, search for information on the Internet and learn:
1. the Oracle database has a maximum number of processes. After logging on to the Oracle database as a DBA user, perform the following operations: SQL> show parameter process; www.2cto.com name type value =----------- aq_tm_processes integer =integer 1gcs_server_processes integer 0job_queue_processes integer =integer 2 processes integer 150 we can see that the current maximum number of connection processes is 150, 150 by default;
2. How can I view the number of current processes? Run the following command: SQL> select count (1) from v $ process; www.2cto.com COUNT (1) ---------- 23. The current number of connection processes is 23.
3. How to configure according to the actual situation? In Oracle8i, because the initialization parameter file only has pfile, It is a notepad. The specific location is ORACLE_BASE \ admin \ ora817 \ pfile \ init. ora (OEACLE_HOME = ORACLEBAE \ ora81), you can open it directly, find the processes keyword, and modify it based on the actual situation. Note that after the modification is complete, you need to restart the service to take effect. After Oracle9i, because the initialization parameter file has spfile, and spfile is a binary file, it cannot be manually modified but can only be modified by using the command. The specific command is as follows: alter system set processes = 200 scope = spfile; note: after the modification, restart the service. After restarting the service, check SQL> show parameter process; NAME TYPE VALUE -------------------------------------- ----------- ----- Q_tm_processes integer 0db_writer_processes integer 1gcs_server_processes integer 0job_queue_processes integer 10log_archive_max_processes integer 2 processes www.2cto.com integer 200. # ORA-01034, ORA-27101 Problems:
When I operate on my machine (Oracle10g), I change the value of processes to 3. When the service is shut down and restarted, it cannot be started normally for a long time. It is suspected that the value of processes is too small, I was lucky enough to manually modify the spfile. This is the end of the Window's servics. the Oracle service cannot be started normally under the msc command. Fortunately, the spfile with processes = 3 is backed up, but physically restored to Windows services. the Oracle service can be started normally under the msc command, but under the cmd command, with DBA user --> sys login, the prompt: ERROR: ORA-01034: oracle not availableORA-27101: shared memory realm does not exist found a lot of information on the Internet, most of which are changed ORACLE_HOME and ORACLE_SID, but my Oracle environment, no problem, ORACLE _ HOME and ORACLE_SID are all normal. I continued to search for information on the Internet and found a good solution based on my actual situation. The idea is: Because my processes value is too small, I cannot manually modify the spfile file directly, as a result, the DBA user cannot log on normally, and thus the spfile parameter value cannot be modified through the command line. In this case, only the spfile is rebuilt through pfile, and then the problematic spfile is replaced with the rebuilt spfile,
The procedure is as follows: www.2cto.com 1. use pfile to reconstruct the spfile and determine the pfile storage path. The pfile storage path is D: \ oracle \ product \ 10.2.0 \ admin \ orcl \ pfile \ init. ora.322201013452 is about to put the new spfile under the root directory of drive d. Therefore, after logging on to the database using DBA user --> sys, run the following command: create spfile = 'd: \ SPFILEORCL. ORA 'from pfile = 'd: \ oracle \ product \ 10.2.0 \ admin \ orcl \ pfile \ init. ora.322201013452 '; 2. after the creation is successful, replace the problematic spfile with the new spfile. The spfile storage path is D: \ oracle \ product \ 10.2.0 \ db_1 \ dbs \ SPFILEORCL. ORA, we recommend that you try to create a new spfile file with the same name as the old one, so that you do not need to modify the content of the pfile. after the replacement is complete, restart the service. Everything is normal. from the column of JavaPeak