Generation of on-demand stats causes subsequent ustats failure

Bug #1394421 reported by Barry Fritchman
6
This bug affects 1 person
Affects Status Importance Assigned to Milestone
Trafodion
In Progress
Medium
Barry Fritchman

Bug Description

When, in the process of optimizing a query, on-demand stats are generated in the form of small-sample histograms, subsequent invocation of Update Statistics fails with an 8415 error (invalid date, time, or timestamp). This appears to be due to an invalid timestamp value within a row inserted into the SB_HISTOGRAMS table when the on-demand stats are created.

This error only recently surfaced, because the quickie stats are not generated unless an estimate of the table's row count is available via HSTableDef::getRowCount(). This function recently began using NATable::estimateHBaseRowCount(), so when it returns a nonzero estimate, and the HIST_ON_DEMAND_STATS_SIZE cqd is set to a value > 0, the code that produces on-demand stats is executed.

Generation of on-demand stats is currently disabled in the code, pending resolution of this issue.

Tags: sql-cmp
Changed in trafodion:
importance: Undecided → Medium
assignee: nobody → Barry Fritchman (barry-fritchman)
Changed in trafodion:
status: New → In Progress
Changed in trafodion:
milestone: none → r2.0
tags: added: sql-cmp
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