Oracle

Oracle Sys users cannot log on with the default password change_on_install (error code: ORA-28009) When you log on to the database using the default Oracle SQL Plus, you can use the system user's default password manager to log on to the

Oracle JOB: 1. Set the initialization parameter job_queue_processes. SQL> alter system set job_queue_processes = n; (n> 0) Job_queue_processes: the maximum value is 1000. View the job queue background process SQL> select name, description from v $

1. If no backup is available: In this case, data may be lost. In this case, you should export the data and review the data in the table for import to restore the damaged data in the data block as much as possible, however, export is not allowed when

MSC + FailSafe dual-host cluster HA SummaryI have recently implemented an Oracle HA application solution. I will summarize it for your reference.　　Hardware configuration:Two Lenovo 82550-wide T630 servers (standard, each server has two intel

Nowadays, Oracle databases are favored by more and more enterprises for their high reliability, security, and compatibility. Readers may wish to consider the following aspects to ensure the permanent performance of Oracle databases. PartitionBased

This article will discuss and share with you some common classic queries of oracle SQL. You are welcome to add them. You can also share some classic queries. In this article, if you think there is any better solution to every problem, you are

Everyone and so on have set the permission. The system rejects the permission, but you still can read it without knowing why. everyone has all the permissions. I used CACLS to change the permission, but there are still problems with restarting, add

SQL> startup mount force;ORACLE instance started. Total System Global Area 2097152000 bytesFixed Size 1268460 bytesVariable Size 704644372 bytesDatabase Buffers 1375731712 bytesRedo Buffers 15507456 bytesDatabase mounted.SQL> alter database

Oracle Bad blocks are divided into Physical Bad blocks and logical Bad blocks, most of which are caused by hardware problems, the cause of logical Bad blocks is generally caused by oracle software bugs or oracle patches not installed.You can use the

8.1 what is an archive log fileOracle databases allow you to store full redo log files to offline directories, which are called archive log files.Archive the process of saving the redo log file to the archive log file. This process can only run in

In Oracle, rownum is the sequence number generated when data is retrieved. Therefore, you must pay attention to the specified rowmun rows of data to be sorted.   SQL> select rownum, id, name from student order by name;   ROWNUM ID NAME   3 200003 Li

Oracle control file recovery case 1: the solution to the loss of a single control file is very simple. Just copy the Multiplexing Control file to the corresponding path. Case 2: All control files are lost (created using SQL in trace) Before this

Oracle knowledge point Summary 3 (subquery) 1. Use of subquery 1. insert use of subquery when inserting data in insert, be sure not to add the Vaules keyword. SQL> create table copy_dep as select * from departments;Table created.SQL> truncate

Monitor the Data Backup recovery progress (EXPDP/IMPDP/RMAN) 1. view the EXPDP/IMPDP progress 1. When you export data, if the data volume is large, some people may be anxious in the middle, but they may want to see how the progress is. You can see

Oracle EM 11g/12c database migration operation 1. overview The Oracle EM11g database needs to be migrated. The main steps are as follows: 1. Disable OMS 2. Back up the current database in the full database, restore to the new server. 3. update the

Oracle-full recovery of user management (iv) I. the role of resetlogs 1. reset the current log serial number to 1, discard all previous log information, you can delete them on the operating system; 2. in non-archive mode, if online redo logs are

In the Oracle RAC environment, the v $ log v $ logfile can query the information of the connected instance in the Oracle RAC environment, the gv $ view contains information about all instances. However, in the RAC environment, when we query the v $

Use AWR to view the SQL Execution Plan. Find the problematic SQL statement in AWR and want to know the specific execution plan of the SQL statement, so I used the SQL id obtained in the AWR report to query several dynamic performance views such as V

Log switch gap and resolvable gap appear in the SWITCHOVER master database. One example is switchover today. The environment is 11.2.0.3 + OEL5.7. At the beginning, the status of the master and slave databases is normal and the direct SWITCH

Oracle forced log archiving archive_lag_target forced archiving forced switching in the Data Guard environment, if the oracle database archiving frequency is too low, resulting in Data loss in the event of a fault, we can use the archive_lag_target