What is patching in oracle?

Patching in oracle is a collecting of regular patches to apply to Oracle products for various purposes including fixing bugs, secure or upgrade. The normal patching workflow can be broken down into the following nice steps:

1. Identify Patches

2. Download Patched and the lastest OPatch utility to a local system

3. Backup to the Oracle Home

4. Identify target

5. Apply on test system

6. Optional create/ update script

7. Check any conflict--> fix it does

8. Test the patches

9. Apply to production

Oracle regularly makes patches available to upgrade features, enhance security, or fix problems with supported software. The major types of patches are:

• Interim patches - contain a single bug fix or a collection of bug fixes provided as required

• Interim patches for security bug fixes - contain customer-specific security bug fixes

• Diagnostic patches - intended to help diagnose or verify a fix or a collection of bug fixes

• Bundle Patch Updates (BPUs) - a cumulative collection of fixes for a specific product or component

• Patch Set Updates (PSUs) - a cumulative collection of high impact, low risk, and proven fixes for a specific product or component and Security Patch Updates

• Security Patch Updates (SPU) - a cumulative collection of security bug fixes. SPUs were formerly known as Critical Patch Updates (CPU).

• System Patch - contains several sub-patches in a format that can be used by OPatchauto.

• Merge Label Request (MLR) - a merge of two or more fixes. MLR creation requires a label for the new set of merged code and a Patch Set Exception

Patching is a set of programs  to fix the problems in the oracle version

Oracle Patch is a program to fix a particular problem, enhance or add a particular feature in the product.

oracle like any software contain bugs which not detected during the testing,

when a bug is detected it is given a unique bug number. oracle fixes the file that is

responsible of the bug.

the new version of the files knows as patch

it is to fix bugs (internal errors) defeats in the s/w code/logic , improve security and add features. 

Patch is a piece of program to fix bugs, improve security or add some features.

Patching is the action of fixing issues or problems that were found by Oracle Corp. using patches issued by Oracle.

It's not always for Bugs, it can also be used for adding options like languages.

Patching is simply bug fixes according to demand of the business users.

PATCH IS PROGRAM (SET OF INSTRUCTIONS) TO FIX A PARTICULAR PROBLEM OR ENHANCE/ ADD A PARTICULAR FEATURE IN EXISTING PROGRAM/PRODUCT/SOFTWARE

Patching is nothing but a bugs fixes.

Any major bugs if you have experienced  in 11.2.0.3 then that would fixes in 11.2.0.4 . Therefore bugs fixes is called as Patching. There are two types of Patching interim patch (for minor bugs)  and patchset patch (for major bugs fixes).