Conversion = 'V' error

I import a big table (lots of columns but less than 4K rows) with a numeric data only (1 column with datetime).
When I try to X-Ray the table (SQL Server), I have the following message :

I try to have a look at the logs :

{:message "Conversion = 'V'",
:type java.util.UnknownFormatConversionException,
:stacktrace
["java.util.Formatter$FormatSpecifier.conversion(Unknown Source)"
"java.util.Formatter$FormatSpecifier.<init>(Unknown Source)"
"java.util.Formatter.parse(Unknown Source)"
"java.util.Formatter.format(Unknown Source)"
"java.util.Formatter.format(Unknown Source)"
"java.lang.String.format(Unknown Source)"
"clojure.core$format.invokeStatic(core.clj:5744)"
"clojure.core$format.doInvoke(core.clj:5738)"
"clojure.lang.RestFn.invoke(RestFn.java:410)"
"--> automagic_dashboards.core$automagic_dashboard.invokeStatic(core.clj:1000)"
"automagic_dashboards.core$automagic_dashboard.invoke(core.clj:986)"
"automagic_dashboards.core$fn__50096.invokeStatic(core.clj:1029)"
"automagic_dashboards.core$fn__50096.invoke(core.clj:1027)"
"api.automagic_dashboards$fn__50450.invokeStatic(automagic_dashboards.clj:113)"
"api.automagic_dashboards$fn__50450.invoke(automagic_dashboards.clj:106)"
"middleware.auth$enforce_authentication$fn__66808.invoke(auth.clj:14)"
"routes$fn__68332$fn__68333.doInvoke(routes.clj:56)"
"middleware.exceptions$catch_uncaught_exceptions$fn__66907.invoke(exceptions.clj:97)"
"middleware.exceptions$catch_api_exceptions$fn__66904.invoke(exceptions.clj:85)"
"middleware.log$log_api_call$fn__68710$fn__68711.invoke(log.clj:197)"
"middleware.log$log_api_call$fn__68710.invoke(log.clj:191)"
"middleware.security$add_security_headers$fn__66870.invoke(security.clj:121)"
"middleware.json$wrap_json_body$fn__68413.invoke(json.clj:64)"
"middleware.json$wrap_streamed_json_response$fn__68431.invoke(json.clj:100)"
"middleware.misc$maybe_set_site_url$fn__68740.invoke(misc.clj:59)"
"middleware.session$bind_current_user$fn__63397$fn__63398.invoke(session.clj:209)"
"middleware.session$do_with_current_user.invokeStatic(session.clj:184)"
"middleware.session$do_with_current_user.invoke(session.clj:177)"
"middleware.session$bind_current_user$fn__63397.invoke(session.clj:208)"
"middleware.session$wrap_current_user_id$fn__63382.invoke(session.clj:161)"
"middleware.session$wrap_session_id$fn__63326.invoke(session.clj:125)"
"middleware.auth$wrap_api_key$fn__66816.invoke(auth.clj:27)"
"middleware.misc$bind_user_locale$fn__68745.invoke(misc.clj:78)"
"middleware.misc$add_content_type$fn__68726.invoke(misc.clj:29)"
"middleware.misc$disable_streaming_buffering$fn__68754.invoke(misc.clj:94)"
"server$async_proxy_handler$fn__68488.invoke(server.clj:70)"
"server.proxy$org.eclipse.jetty.server.handler.AbstractHandler$ff19274a.handle(Unknown Source)"]}

Hi @nico8
Please post “Diagnostic Info” from Admin > Troubleshooting.
I’ve never seen that error before. Is V a column in your table?
You would likely need to enable debug logging to figure out what’s going wrong:
https://www.metabase.com/docs/latest/operations-guide/log-configuration.html

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    "vendor": "Apple Computer, Inc."
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    "java.version": "1.8.0_221",
    "java.vm.name": "Java HotSpot(TM) 64-Bit Server VM",
    "java.vm.version": "25.221-b11",
    "os.name": "Windows Server 2016",
    "os.version": "10.0",
    "user.language": "en",
    "user.timezone": "Europe/Paris"
  },
  "metabase-info": {
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    "run-mode": "prod",
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No column named « V »

I activate the DEBUG mode but no more info.
I inspect the columns name and it seems that there was a pourcentage % at the begining of some columns. I replace the % by P and X-ray works !

@nico8 Excellent information. And great that you found a workaround.
It sounds very similar to this issue (see the bottom comments):
https://github.com/metabase/metabase/issues/12337

I’ve opened an issue to track this: https://github.com/metabase/metabase/issues/12592 Thanks for reporting and figuring out the root cause1