I faced the same problem migration of 1.9.10 to 1.9.14.
Steps of my installation:
1. previously installed version is 1.9.10 bitnami testlink.
2. Download the latest Bitnami testlink 1.9.14
3. Took a DB backup using the root user name
4. Uninstalled the previous version 1.9.10
5. Installed the latest version 1.9.14
6. Opened the DB as a root user for 1.9.14
7. Imported the backup SQL file
8. Now tried to login as an admin.
9. Observed error was "Unknown Schema version DB 1.9.9, please upgrade your Testlink Database to DB 1.9.14".
Now, how to take a back up of previous version and upload in the new installed testlink 1.9.14 ?
The backup very important because all the execution history and test cases history is present in the older version.
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