fix(vdiff): preserve PK definition order in getSourcePKCols - #905
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pedroalb wants to merge 1 commit into
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fix(vdiff): preserve PK definition order in getSourcePKCols#905pedroalb wants to merge 1 commit into
pedroalb wants to merge 1 commit into
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The getSourcePKCols function put PrimaryKeyColumns into a map (losing order) then iterated td.table.Columns in ORDINAL_POSITION order. This produced sourcePkCols in column ordinal order rather than PK definition order (SEQ_IN_INDEX). On VDiff resume, VStreamRows receives the wrongly-ordered lastpk values and the row streamer pairs them positionally with its own pkColumns (which ARE in correct SEQ_IN_INDEX order). This corrupts the WHERE clause and generates false ExtraRowsSource/ExtraRowsTarget reports. Fix: build a column-name-to-index map and iterate PrimaryKeyColumns in definition order, preserving SEQ_IN_INDEX ordering. Upstream PR: vitessio#20603 Related issue: vitessio#20601 Signed-off-by: Pedro Albuquerque <pedroalb@gmail.com> Signed-off-by: Pedro Albuquerque <pedro.albuquerque@slack-corp.com>
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Summary
getSourcePKColsto preserve PK definition order (SEQ_IN_INDEX) instead of column ordinal positionRoot Cause
getSourcePKColsputPrimaryKeyColumnsinto amap[string]struct{}(losing order), then iteratedtd.table.ColumnsinORDINAL_POSITIONorder. On VDiff resume,VStreamRowsreceives the wrongly-orderedlastpkvalues and the row streamer pairs them positionally with its ownpkColumns(which ARE in correct SEQ_IN_INDEX order fromBaseShowPrimary). This corrupts the WHERE clause.Fix
Replace the map+ordinal-scan with a column index lookup that preserves PK definition order.
Impact
Only affects tables where PK column order differs from column ordinal position AND VDiff resumes (via
max-diff-durationtimeout, auto-retry, or manual resume). Single uninterrupted VDiff passes are unaffected.Test Plan
TestSourcePKColsOrderingregression test with 4 casesReferences