Understanding how oracle internally manages the transactions is very crucial for your applications. Dealing with the database as a black box (sending queries and receiving results), will end up with bad performance to your application or/and non-scalable application. Oracle uses locks to internally manages the concurrent access to data.Only one transaction can modify any piece … Continue reading Oracle Database Locking Policy – Back to Basics
https://youtu.be/qsepeUPQ-JU For more information on how to get this VM and other similar machines, please refer to:https://ahmedfattah.com/2020/06/13/oracle-virtual-machines-for-sale/ ThanksAhmed
Are you looking for a virtual machine to do some hands-on labs or practice something (i.e. for Educational purposes}? Do you have the time to build these virtual machines yourself? Below are some really nice Virtual Machines, that I invested allot of time to build on Oracle Virtual Box, and that I used them personally … Continue reading Oracle Virtual Machines for Sale !
While trying to open one pluggable database, I got the following errors: Background: While installing Apex 20.1 in one PDB, and while being very close to the installation completion, the session fully stucked.I restarted the database (the CDB), then I tried to open the PDB, but I got the above errors. While searching for this … Continue reading Alter Pluggable Database Open – (ORA-00604/ORA-01405) After Apex Installation
This is a quick post about an issue that I faced while trying to start one database yesterday. When I was trying to open one 12cR1 database, I got the following error: SYS SQL>alter database open;alter database open*ERROR at line 1:ORA-38760: This database instance failed to turn on flashback database The database status was "mounted": … Continue reading ORA-38760 While starting an Oracle Database
I got this question from one of my clients. He is going to migrate one database from one platform to another. In this database many users are sharing the same tablespace. For example: In the current database, all application users are sharing the tablespaces “USERS” The client wants to change this, so as each schema … Continue reading Is it possible to map one Tablespace to many Tablespaces with impdp?
Oracle Database 20c is now Generally Available on the cloud two days ago, 14-Feb-2020. Oracle 20c is next major database release. It includes many new fetaures espcially in the following areas: BlockchainMachine LearningSecurityJSONIn-Memory For a quick introduction to this new release:https://blogs.oracle.com/database/ga-of-oracle-database-20c-preview-release Also, for complete list of the new features, please refer to the:https://docs.oracle.com/en/database/oracle/oracle-database/20/newft/new-features.html Oracle Database … Continue reading Oracle Database 20c is now Generally Available
Below may be the longest SQL statement that I have ever seen. I don't know if it is written by one developer or group of developers and what is the logic behind it? I really don't like this style of writing sql statements. It is very difficult to be functionally understood. Also, it is very … Continue reading The Longest SQL Statement I have ever seen !