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Error : The DBSNMP user is locked after a certain period of time. Reason: An application (possibly an application in EM) is trying to login …

Description: Drop tables is such a common content of a DBA’s daily work. Drop a small table( such as less than 100 Mega Bytes ), we …

  With using triggers in PostgreSQL, you can trigger another event before an event occurs (BEFORE TRIGGER). Or you can trigger another event after it …

Description: Recently, when i checked my data on two MySQL servers( version: 5.7.17 ), i found data differences between to servers, which surprised me. Because …

  pt-online-schema-change is a binary part of Percona-toolkit packages by Percona. It’s one of the most stable and efficient, tools for performing large MySQL table structure change in …

  Do the operating systems kill your MySQL instances from time to time? Are some database servers swapping constantly? These are relatively common problems. Why? …

  12c R1 Has a New Feature to suppress the generation of redo during Data Pump import. This feature not only suppresses the redo generation …

  NoSQL databases are highly scalable and flexible database management systems which allow you to store and process unstructured as well as semi-structured data which …

Note: First try below steps on test or non-prod server. Keep software ready and accessible. root access required to install binaries. create new mount point …

Error: During RMAN backup, you can see the following errors. ORA-00245: control file backup operation failed RMAN-08132: WARNING: can not update recovery area reclaimable file …