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Connor McDonald

Thanks for the question, Oleksii.

Asked: June 28, 2016 - 11:11 pm UTC

Answered by: Connor McDonald - Last updated: June 29, 2016 - 4:06 am UTC

Category: Developer - Version: 12c

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You Asked


The Oracle error messages are not always very descriptive. Searching the internet I found couple reasons why we can get ORA-12560 error:
1) Oracle database instance is not started
2) ORACLE_HOME is not set (for version 10)

What are other possible meanings of this error can be?
In my case I use OCCI API to connect to the database (the same connection string works for SQL PLUS) and set correct ORACLE_HOME and instance is running (version is 12c).
Is it kind of generic error? What is the real meaning of this error?

and we said...

It's "generic" in the sense that we couldnt get far enough to get a precise cause of the issue.

It's like if you want to go to the shops. The *possible* problems might be:

- shop is closed
- shop does not have your item
- shop is being robbed
- no parking spaces available

but "ORA-12560: TNS:protocol adapter error" is like saying "The car wont start" so I cant even begin to *get* to the shops, let alone know what potential problems might be waiting.

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