Fix missing null check and wrong cast in TimestampType comparisons#883
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Chessing234 wants to merge 1 commit intocmu-db:masterfrom
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Fix missing null check and wrong cast in TimestampType comparisons#883Chessing234 wants to merge 1 commit intocmu-db:masterfrom
Chessing234 wants to merge 1 commit intocmu-db:masterfrom
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1. CompareNotEquals: missing left.IsNull() check. Only right.IsNull() is checked, so comparing a NULL left timestamp against a non-NULL right returns CmpTrue/CmpFalse instead of CmpNull, violating SQL null semantics. Every other Compare* method checks both sides. 2. CompareGreaterThan: uses int64_t instead of uint64_t. Timestamps are stored as uint64_t; signed comparison causes large timestamp values (bit 63 set) to be treated as negative, inverting the ordering. Every other Compare* method uses uint64_t. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Two correctness bugs in
timestamp_type.cpp:1.
CompareNotEqualsmissingleft.IsNull()check (line 34)Only
right.IsNull()is checked. Ifleftis NULL andrightis not, the function reads the NULL value's bit pattern and returnsCmpTrue/CmpFalseinstead ofCmpNull. This violates SQL null semantics (NULL != xmust beNULL). Every otherCompare*method in this file checksleft.IsNull() || right.IsNull().2.
CompareGreaterThanusesint64_tinstead ofuint64_t(line 61)Timestamps are stored as
uint64_t. Signed comparison viaint64_tcauses values with bit 63 set to be interpreted as negative, inverting the ordering for large timestamps. Every otherCompare*method usesuint64_t.Test plan
uint64_tstorage (value_.timestamp_, SerializeTo, DeserializeFrom)