Metadata queries


my SQL queries on metadata tables do not return anything.

return empty datasets

It is the case in 4.0.2 and in 4.0.5.
Am I alone in this case ?



Works as expected. Would you be able to run the query and send us the profile? Also can you check if the server.log has any exceptions?


The query is as above ,


here is the profile (6.2 KB)

and no exception in server.log

2019-11-26 13:48:00,269 [out-of-band-observer] INFO query.logger - {“queryId”:“2222d2f0-3e76-65b6-5cb3-0f4480c22a00”,“schema”:"[@david]",“queryText”:“select * from INFORMATION_SCHEMA.VIEWS”,“start”:1574776079913,“finish”:1574776080268,“outcome”:“COMPLETED”,“username”:“david”}


We experience similar issues and expect a fix. In fact it works if the query doesn’t return a large number of records …note : We are running Enterprise edition. Case is open for quite a long time and wait patiently to be fixed.

Thanks ! So it seems to happen only when there is a large number of VDS , etc… ?
I tried to reduce the number of results by filtering eg
where TABLE_NAME like ‘C%’ or using the LIMIT clause.

but still I get no results. Did you find any trick ?

Do you get this error in the Profile -> Error? I managed to dig up the error below after some digging through profiles and Yarn logs:

dataset listing failed: java.util.concurrent.TimeoutException

For us the root cause was a hard coded RPC timeout, which comes into play when your executor is not on the same server as your coordinator (in our case a Yarn executor cluster). When this happens the dataset listing query executes over RPC on the coordinator; vs when the executor and coordinator are the same box and it executes locally (which has no timeout).


final ProtocolBuilder builder = ProtocolBuilder.builder()
    .timeout(10 * 1000);

The above code sets a hard coded timeout of 10 seconds. We found that with large numbers of VDS, some queries take 4 minutes to complete over RPC, though only a few seconds when the coordinator and executor are the same box. We are working to expose this timeout as a support key in our local code base.


I see there are no files that Dremio is reading. Does INFORMATION_SCHEMA.“TABLES” return results?


@balaji.ramaswamy could you explain what you mean by return results?

Both queries

return no results, with no error, and immediately


I assume you have datasets in these sources? Try this. Shutdown the executor and the coordinator then “cd DREMIO_HOME/bin” and run “./dremio-admin clean” and send us the output

Restart coordinator and then the executors


Of course I have an important number of datasets in these sources (several hundreds)

thanks, here the output of the command dremio-admin clean (999 Bytes)

Hi @balaji.ramaswamy , are there any news on this topic ?


Let’s do this,

Do a run (not preview) of the below SQL and send me the profiles

select * from information_schema.“tables”
select * from information_schema.views

Share a query profile

here they are
select * from information_schema.“tables” (6.3 KB)

select * from information_schema.views (6.3 KB)


Other than this issue ,are you able to see all your datasets on the UI and do they work as expected?


Well, it’s difficult to say, as I have hundreds of datasets, so I can not test all of them in the UI.
but in my day to day activity in the UI, I do not have issues in the UI, they work as expected.

Hi Rama, Can I understand, Once I update the table/view structure, such as new view created, new column adding, or column data type change, the metadata table INFORMATION_SCHEMA.COLUMNS will get the timely update ASAP? For example, how much time I can see the updated metadata after my structure change of my view? thanks!


I have answered your other post on the same question