Summary

When a partial insert has failed measurements (\measurements[i] == null), the \pointsInserted\ counter could go negative in two paths:

1. **\AbstractMemTable.insertAlignedRow**: a failed measurement slot has both \measurements[i] == null\ and values[i] == null. The old guard \if (values[i] == null)\ did not check \measurements[i]\ first, so the null value was counted as a
   ullPoint\ and subtracted from the total, producing a negative result.

2. **\AbstractMemTable.computeTabletNullPointsNumber**: failed measurement columns were not skipped before inspecting their bitmaps, so any marked bits in a failed column were incorrectly counted as null points.

Changes

• **\InsertNode.java**: add \isMeasurementFailed(int index)\ helper that returns \measurements[index] == null.
• **\AbstractMemTable.java**:
  • \insertAlignedRow: change guard to \measurements[i] != null && values[i] == null\ so failed measurements are excluded from
    ullPointsNumber.
  • \computeTabletNullPointsNumber: skip columns where \isMeasurementFailed(i)\ is true before counting bitmap marks.

Tests

• **\InsertNodeIsMeasurementFailedTest**: unit tests for the new \isMeasurementFailed\ method on both \InsertRowNode\ and \InsertTabletNode, covering no-failure, single failure, all-failed, and idempotent mark cases.
• **\AbstractMemTablePartialInsertTest**: unit tests for \insertAlignedRow\ and \insertTablet\ with precise \AssertEquals\ assertions on \pointsInserted\ and \ otalPointsNum, covering all combinations of failed measurements and null bitmaps.