With using triggers in PostgreSQL, you can trigger another event before an event occurs (BEFORE TRIGGER). Or you can trigger another event after it …
Read More »MySQL — The DATETIME column rounding causes data inconsistency
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 …
Read More »Alter large MySQL table without blocking reads or writes with pt-online-schema-change
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 …
Read More »MySQL Crashed by OOM Killer (out of memory). Why? How to prevent them?
Do the operating systems kill your MySQL instances from time to time? Are some database servers swapping constantly? These are relatively common problems. Why? …
Read More »How To Make IMPDP Faster Using Oracle 12c New Feture
12c R1 Has a New Feature to suppress the generation of redo during Data Pump import. This feature not only suppresses the redo generation …
Read More »What is NoSQL?
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 …
Read More »DB2 Database upgrade from db2 9.7 to db2 11.1
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 …
Read More »RMAN-08132: WARNING: cannot update recovery area reclaimable file list
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 …
Read More »How To Install MySQL 5.7 Community on Ubuntu
Introduction MySQL, the most popular Open Source SQL database management system developed, distributed, and supported by Oracle Corporation. In this article we’ll go over …
Read More »RMAN Commands Hanging
Error: When connecting to RMAN, it generates output when any command is given, but the command is not completed and is waiting. Reason: Disruption in …
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