DictionaryEncodedColumnPartSerde: Read values using smooshReader. #17688
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The write side uses a FileSmoosher for valueWriter, which means that the value component may be split over multiple files. In this case, the read side needs a SmooshedFileMapper. It is plausible for multi-valued columns to have value sections in excess of 2 GB: imagine a segment with 10 million rows and an average of 50 values per row. The value section would have 500 million ints, which is 2 GB.
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Marking draft since the patch should have a test. |
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Btw, I think the same basic problem exists in |
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Closing in favor of #17691. |
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The write side uses a FileSmoosher for
valueWriter, which means that the value component may be split over multiple files. In this case, the read side needs a SmooshedFileMapper.It is plausible for multi-valued columns to have value sections in excess of 2 GB: imagine a segment with 10 million rows and an average of 50 values per row. The value section would have 500 million ints, which is 2 GB.
I believe this is the cause of #7943.