# External Reflection issue

**URL:** <https://community.dremio.com/t/external-reflection-issue/5166>\
**Category:** Uncategorized\
**Created:** [March 5, 2020, 10:19am UTC](https://community.dremio.com/t/external-reflection-issue/5166 "2020-03-05T10:19:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![elshafey](https://sea2.discourse-cdn.com/flex020/user_avatar/community.dremio.com/elshafey/32/2009_2.png) [@elshafey](https://community.dremio.com/u/elshafey)\
**Post date:** [March 5, 2020, 10:19am UTC](https://community.dremio.com/t/external-reflection-issue/5166/1 "2020-03-05T10:19:00Z")

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I got that error while trying to create an external reflection

SYSTEM ERROR: NullPointerException  
(com.dremio.exec.work.foreman.ForemanException) Unexpected exception during fragment initialization: java.lang.NullPointerException  
com.dremio.exec.work.foreman.AttemptManager.run():371  
java.util.concurrent.ThreadPoolExecutor.runWorker():1149  
java.util.concurrent.ThreadPoolExecutor$Worker.run():624  
java.lang.Thread.run():748  
Caused By (java.util.concurrent.ExecutionException) java.lang.NullPointerException  
java.util.concurrent.CompletableFuture.reportGet():357  
java.util.concurrent.CompletableFuture.get():1908  
com.dremio.exec.work.foreman.AttemptManager.run():326  
java.util.concurrent.ThreadPoolExecutor.runWorker():1149  
java.util.concurrent.ThreadPoolExecutor$Worker.run():624  
java.lang.Thread.run():748  
Caused By (java.lang.NullPointerException) null  
com.dremio.service.reflection.ReflectionUtils.computeDatasetHash():138  
com.dremio.service.reflection.ReflectionServiceImpl.createExternalReflection():485  
com.dremio.service.reflection.AccelerationManagerImpl.addExternalReflection():177  
com.dremio.exec.planner.sql.handlers.direct.AccelAddExternalReflectionHandler.toResult():48  
com.dremio.exec.planner.sql.handlers.commands.DirectWriterCommand.plan():99  
com.dremio.exec.work.foreman.AttemptManager.plan():421  
com.dremio.exec.work.foreman.AttemptManager.lambda$run$0():324  
com.dremio.service.commandpool.CommandWrapper.run():62  
java.util.concurrent.ThreadPoolExecutor.runWorker():1149  
java.util.concurrent.ThreadPoolExecutor$Worker.run():624  
java.lang.Thread.run():748  
and here is the job profile[4322879f-3e6a-4b1a-975a-fe4215779662.zip](https://community.dremio.com/uploads/short-url/2ps037l2Z6BSJ7bUpodtM80FNxl.zip) (4.4 KB)

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**Author:** ![doron](https://sea2.discourse-cdn.com/flex020/user_avatar/community.dremio.com/doron/32/294_2.png) [@doron](https://community.dremio.com/u/doron)\
**Post date:** [March 6, 2020, 4:19pm UTC](https://community.dremio.com/t/external-reflection-issue/5166/2 "2020-03-06T16:19:57Z")

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Can you query `"S3 Storage".Forasna."Shafey Experiments".Views."test-external-reflections"` and `"@elshafey"."vds-with-external-reflection"`successfully as is?

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<div class="post-metadata">

**Author:** ![elshafey](https://sea2.discourse-cdn.com/flex020/user_avatar/community.dremio.com/elshafey/32/2009_2.png) [@elshafey](https://community.dremio.com/u/elshafey)\
**Post date:** [March 22, 2020, 1:23pm UTC](https://community.dremio.com/t/external-reflection-issue/5166/3 "2020-03-22T13:23:11Z")

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I tried to query both datasets and everything worked properly