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Third, run all the existing Impala test to ensure your fix doesn't introduce any new issues. See for How to load and run Impala tests for more details.
Fourth, please keep your patch narrowly targeted to the problem described by the JIRA. It’s better for everyone if we maintain discipline about the scope of each patch. In general, if you find a bug while working on a specific feature, file a JIRA for the bug, check if you can assign it to yourself and fix it independently of the feature. This helps us to differentiate between bug fixes and features and allows us to build stable maintenance releases.
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