A Beginner question on Metabase via Docker

Hi everyone,
I have installed Metabase 0.44 on my Synology NAS via Docker to analyze my ERP (running on the NAS on MariaDB10) few weeks ago and started building questions, love the program so far!

I want to upgrade to 0.45 but realize I'm not clear with the explanations from the "Upgrading Metabase" page. Since I have already linked my ERP DB to Metabase (and deleted the H2 database):

  1. are my questions and Metabase setup automatically stored on the ERP's DB, or are they somewhere else in Docker?
  2. is it safe then to upgrade to 0.45 directly, or should I save the Metabase setup first (and how)?

Many thanks in advance and sorry to ask such a simple question!

Hi @BenTpe
Without knowing how you have setup Metabase initially, then it's difficult to say.
All Metabase data is stored in the "application database":

Post "Diagnostic Info" from Admin > Troubleshooting.

Hi Flamber,
sorry for very delayed answer! Here is diagnostic info, I see there is still an H2 database, although I had deleted it from tables. I see the instructions to upgrade from Docker but don't really understand how to do, will ask a professional to do it for me, thanks for your answer.
"browser-info": {
"language": "en-US",
"platform": "MacIntel",
"userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.2 Safari/605.1.15",
"vendor": "Apple Computer, Inc."
"system-info": {
"file.encoding": "UTF-8",
"java.runtime.name": "OpenJDK Runtime Environment",
"java.runtime.version": "",
"java.vendor": "Eclipse Adoptium",
"java.vendor.url": "https://adoptium.net/",
"java.version": "",
"java.vm.name": "OpenJDK 64-Bit Server VM",
"java.vm.version": "",
"os.name": "Linux",
"os.version": "4.4.180+",
"user.language": "en",
"user.timezone": "GMT"
"metabase-info": {
"databases": [
"hosting-env": "unknown",
"application-database": "h2",
"application-database-details": {
"database": {
"name": "H2",
"version": "1.4.197 (2018-03-18)"
"jdbc-driver": {
"name": "H2 JDBC Driver",
"version": "1.4.197 (2018-03-18)"
"run-mode": "prod",
"version": {
"date": "2022-09-02",
"tag": "v0.44.3",
"branch": "release-x.44.x",
"hash": "7d50282"
"settings": {
"report-timezone": null

What this means is that the H2 database is the current application database. You need to first migrate from H2 to Postgres or MySQL (so you take the data out of the container) and then you can upgrade the current Metabase

Hi @Luiggi thanks for your answer!
Yes, I'm clear with the conceptual idea, just not too sure how to do it as there is a terminal in docker, but it doesn't seem to react to my commands, and I'm not sure how to connect the mySQL data then... will work on it!