Upgrading Oracle 11.2.0.1 to 11.2.0.4

I have a 11g R2 DB running on Windows 2012 (11.2.0.1) and I need to apply patch and/or psu to get 11.2.0.4

I've been a DBA for many years but principally focused on performance tunning and development, this is the first time I need to patch a DB for myself.

For the beggining, could someone explain me the difference between a Patch and a PSU?, I found the following link where it containts all patches and PSU's available, but don't know which exactly I need to use for going from 11.2.0.1 to 11.2.0.4 (the table for 11.2.0.4, I guess?).

Any help is appreciated.

Regards

David Ramírez Reyes

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