Foglight Postgresql Embedded database repository should not be upgraded manually. Remember upgrading Foglight embedded DB repository to an unsupported version can cause a problem.
If you want to handle your own DB upgrade cycle, you can migrate to external DB. Remember Foglight - System Requirements and Platform Support Guide shows the supported Postgresql version of the current Foglight you are running.
Reference: Switching from an embedded PostgreSQL to an external PostgreSQL database
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