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Bug reports are best when they contain a precise description of the problem, a minimal set of steps to reproduce the issue, and a comprehensive description of your environment (what version of Impala are you running? Are you using HDFS, S3 or HBase?)
Please do not create JIRA tickets for general user or developer questions - direct those to the appropriate mailing list - https://impala.apache.org/community.html
Code
As with other open source communities, the best way to engage is to start small, by fixing some bugs or contributing small features. By doing so, you will earn a reputation as a contributor of high-quality patches, you will get to know the Impala community, and you will become familiar with our process for contribution.
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