How can I get data from the OpenTelemetry collector into PostgreSQL?

[FelixZY]

Note: this is a copy of my question on stack overflow

I'm trying to learn about OpenTelemetry. My understanding so far is that my services will send data to the OpenTelemetry collector, which will in turn pass this data on to e.g. jaeger or zipkin from which I can then visualize the data in a web UI.

However, this seems a bit fragile to me - what if I want to change to another tool in the future? How would I import my old data to this new tool? It seems to me it would be a good idea to save the collected data to my own database (using a PostgreSQL "exporter"?). This way, the data would also be available for direct use by my services.

Unfortunately, I'm not able to find any information on how to store metric data in PostgreSQL, only a bunch of tutorials on how to collect metrics from it. So: how can I get data from the OpenTelemetry collector into PostgreSQL?