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https://issues.apache.org/jira/browse/IMPALA-7586?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16665765#comment-16665765
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Tim Armstrong commented on IMPALA-7586:
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I can pick this up for the release since I know what's going on.
> Incorrect results when querying primary = "\"" in Kudu
> ------------------------------------------------------
>
> Key: IMPALA-7586
> URL: https://issues.apache.org/jira/browse/IMPALA-7586
> Project: IMPALA
> Issue Type: Bug
> Components: Frontend
> Affects Versions: Impala 3.1.0
> Reporter: Will Berkeley
> Assignee: Tim Armstrong
> Priority: Blocker
> Labels: correctness, kudu
> Attachments: impalakudu_pred_bug.profile
>
>
> Version string from catalogd web ui:
> {noformat}
> catalogd version 3.1.0-cdh6.x-SNAPSHOT RELEASE (build
> 8baac7f5849b6bacb02fedeb9b3fe2b2ee9450ee)
> {noformat}
> A reproduction script for the impala-shell:
> {noformat}
> create table test(name string, primary key(name) ) stored as kudu;
> insert into test values ("\"");
> -- Modified 1 row(s), 0 row error(s) in 4.01s
> -- row found in full table scan
> select * from test;
> -- Fetched 1 row(s) in 0.15s
> -- row not found on = predicate (pushed to kudu)
> select * from test where name="\"";
> -- Fetched 0 row(s) in 0.13s
> -- row found when predicate cannot be pushed to kudu
> select * from test where name like "\"";
> -- Fetched 1 row(s) in 0.13s
> {noformat}
> This was originally reported as KUDU-2575. I tried to reproduce directly
> against Kudu using the python client but got the expected result.
> From the plan and profile, Impala is pushing down the predicate, but Kudu is
> not being scanned, possibly because the Kudu client short-circuits the scan
> as having no results based on the predicate Impala pushes down.
> {noformat}
> 00:SCAN KUDU [default.test]
> kudu predicates: name = '"'
> mem-estimate=0B mem-reservation=0B thread-reservation=1
> tuple-ids=0 row-size=15B cardinality=unavailable
> in pipelines: 00(GETNEXT)
> {noformat}
> {noformat}
> KUDU_SCAN_NODE (id=0)
> - AverageScannerThreadConcurrency: 0.00 (0.0)
> - InactiveTotalTime: 0ns (0)
> - KuduRemoteScanTokens: 0 (0)
> - MaterializeTupleTime(*): 0ns (0)
> - NumScannerThreadMemUnavailable: 0 (0)
> - NumScannerThreadsStarted: 1 (1)
> - PeakMemoryUsage: 24.0 KiB (24576)
> - PeakScannerThreadConcurrency: 1 (1)
> - RowBatchBytesEnqueued: 16.0 KiB (16384)
> - RowBatchQueueGetWaitTime: 0ns (0)
> - RowBatchQueuePeakMemoryUsage: 0 B (0)
> - RowBatchQueuePutWaitTime: 0ns (0)
> - RowBatchesEnqueued: 1 (1)
> - RowsRead: 0 (0)
> ===> - RowsReturned: 0 (0)
> - RowsReturnedRate: 0 per second (0)
> - ScanRangesComplete: 1 (1)
> - ScannerThreadsInvoluntaryContextSwitches: 0 (0)
> - ScannerThreadsTotalWallClockTime: 0ns (0)
> - ScannerThreadsSysTime: 158.00us (158000)
> - ScannerThreadsUserTime: 0ns (0)
> - ScannerThreadsVoluntaryContextSwitches: 2 (2)
> ===> - TotalKuduScanRoundTrips: 0 (0)
> - TotalTime: 1ms (1999972)
> {noformat}
> I also confirmed Kudu sees no scan from Impala for this query using the
> /scans page of the tablet servers.
> Full profile attached.
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