ORACLE

enq: TX – row lock contention can be regarded as a row lock conflict wait event in operations. This event indicates that a session is …

  Latch free and library cache: mutex X wait events can be seen for the corresponding SQL statements in intensive delete and insert operations in …

In 12c databases, ORA-12805, ORA-07445 [qertqistart] or ORA-600 [15803] errors may occur depending on bug 25694206. User operation cannot be completed due to the closing …

  If an oracle user is locked, it is usually caused by an incorrect password entry. In some cases, even if you remove the user’s …

  On an Oracle RAC server, you may receive an error as follows when you want to create a new database with runinstaller. INS-35354: The …

  When the “AVDF transaction log audit trail” is created and deleted, the archive logs cannot be deleted normally, depending on bug 23217905. The problem …

With ADRCI, it is possible to delete files such as “log, trace, incident, cdump” created before a certain day. Instead of manually deleting individual files, …

  There may be a slowdown when you query dba_free_space or tablespaces via Toad on 12C databases. The slowness is due to the fact that …

You can see “WARNING: AQ_TM_PROCESSES is set to 0. System operation might be adversely affected.” warnings at certain intervals in the database alert log file. …

  If the RMAN restore hangs with the “starting implicit crosscheck backup” error and has not been completed for a long time, you may have …