Author Archives: mgogala

About mgogala

I am a consultant with an extensive Oracle DBA experience. I have worked on very large databases. I have worked with OPS and RAC since its inception.I am also a published book writer, having published two books about PHP. This blog is about the challenges and adventures in my professional life. Sorry, no family pictures here.

Upgrade to Oracle problems

I was recently tasked with upgrading  an Oracle RDBMS to The platform is Windows 2012 R2. I know about not being able to move the listener to the new 12c home, which prevents me from using the upgrade … Continue reading

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SAP Hana is becoming increasingly popular these days. It comes with its own demo schema, STUDENT. However, being an old Oracle hack, I ported the SCOTT schema from Oracle to SAP Hana. Every Oracle DBA has a bunch of queries … Continue reading

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Finding the trace files

In Oracle versions before 12c, it was necessary to resort to complex magic to find out the location of the process trace file. One of the most famous recipes is probably the one invented by René Nyffenegger and available here: reading

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ACFS 12.2 Quirks with defragmentation

I have a 12.2 RAC cluster in my lab, on two virtual machines. Checking out what acfsutil can do, I figured out that it can supposedly do defragmentation: [grid@rac1 ~]$ acfsutil defrag -help Usage: acfsutil [-h] command … # (Version … Continue reading

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RAC 12.2, part 2

Well, today was an interesting day. My ASM, configured with so much effort, stopped working: root@rac1 grid]# . ~grid/.bashrc [root@rac1 grid]# crsctl start ohasd CRS-4640: Oracle High Availability Services is already active CRS-4000: Command Start failed, or completed with errors. … Continue reading

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RAC 12.2

I am in the process of installing RAC 12.2. The installation procedure has undergone a significant change, for the better. It’s now much easier to install it. However, memory and disk requirements have skyrocketed. I needed to allocate 10GB of … Continue reading

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Rename Pluggable Database

I stumbled upon a convenient way to rename a pluggable database: SQL> alter system enable restricted session; System altered. SQL> alter database rename global_name to; Database altered. SQL> alter session set container=cdb$root; Session altered. SQL> select name from v$pdbs; … Continue reading

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