feat: add support for blind appends #3890
Draft
+31
−2
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Description
Consider the following case:
This will fail, since by default, the conflict checker assumes that the write depended on all the files in the table at a given state, this with
ConcurrentDeleteRead. However, if it is a true blind append, the writer never depended on the state of the table.Instead, this PR marks a write commit as a blind append if it is in mode Append and there are no remove actions.
Marked as draft bc I'd like to write tests and confirm this is the correct behavior.
Related Issue(s)
Likely closes #2700
Documentation
Reference here: https://books.japila.pl/delta-lake-internals/OptimisticTransactionImpl/?h=blind+app#isBlindAppend
Planning on diving into the delta-spark code when I have the time to ensure this is the correct heuristic.