Fix bug when prefix_same_as_start = true and keys not in domain #5923
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Summary: Prefix extractor needs to be invoked for a key only when it is in domain. However, when prefix_same_as_start = true, this assumption is broken. The fix is to add InDomain() check before any Transform() call when prefix_same_as_start = true. Test Plan: Add a unit test to cover prefix_same_as_start = true with seek keys and keys on DB not in domain.
| assert(prefix_extractor_ != nullptr); | ||
| assert(!prefix_same_as_start_ || prefix_extractor_ != nullptr); | ||
| if (valid_ && prefix_same_as_start_ && | ||
| prefix_extractor_->InDomain(saved_key_.GetUserKey())) { |
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If valid_, can prefix_extractor_->InDomain(saved_key_.GetUserKey()) be false?
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If |
| ro.prefix_same_as_start = true; | ||
| std::unique_ptr<Iterator> iter(NewIterator(ro)); | ||
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| // Behavior of prefix_same_as_start = ture with seek key not in domain |
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Yeah, this is one of the cases I was thinking about where we could consider making the iterator invalid.
Also, there's a typo ("true").
| ASSERT_FALSE(iter->Valid()); | ||
| ASSERT_OK(iter->status()); | ||
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| // Behavior of prefix_same_as_start = ture + SeekForPrev() is not defined |
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Same here; also, it's SeekToFirst/SeekToLast, not SeekForPrev. (We could also consider actually adding a test for say, SeekForPrev("e").)
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hi, Any updates in this issue ? we have used PrefixExtractor, but not all keys meet the InDomain of PrefixExtractor. When we enable total_ order_ seek, but prefix_same_as_ start still on, follow the comments in ReadOptions, prefix_same_as_ start=true && total_ order_ seek=true, prefixScan is not effective. However, when the Iterator is actually used, the process will be aborted because the traversal does not meet the InDomain constraint~ |
Summary: Prefix extractor needs to be invoked for a key only when it is in domain. However, when prefix_same_as_start = true, this assumption is broken. The fix is to add InDomain() check before any Transform() call when prefix_same_as_start = true.
Test Plan: Add a unit test to cover prefix_same_as_start = true with seek keys and keys on DB not in domain.