fix(nimble): Keep nulls in dictionary reads without AVX2 (#18621) - #18621
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fix(nimble): Keep nulls in dictionary reads without AVX2 (#18621)#18621Yuhta wants to merge 1 commit into
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…ubator#18621) Summary: Reading a Nimble string column that keeps its dictionary encoding dropped every null on any platform where `process::hasAvx2()` is false, which is all of aarch64. A 200-row column holding `always_the_same` with a null every 7th row came back as a `DictionaryVector` carrying no null flags, so row 0 read as `always_the_same` instead of null. The dense dictionary-index path wrote nulls only into the reader's read-range bitmap. It then relied on `returnReaderNulls_` to hand that bitmap back from `resultNulls()`. `setReturnNullsMode` clears that flag whenever `useBulkPath()` is false, and `process::hasAvx2()` makes that permanent off AVX2. `resultNulls()` then returns the output-indexed buffer instead, which nothing on this path filled. It now copies the read-range nulls into that buffer, the way the sparse row-set path already did. Reviewed By: vandreykiv Differential Revision: D116833280
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…ubator#18621) Summary: Reading a Nimble string column that keeps its dictionary encoding dropped every null on any platform where `process::hasAvx2()` is false, which is all of aarch64. A 200-row column holding `always_the_same` with a null every 7th row came back as a `DictionaryVector` carrying no null flags, so row 0 read as `always_the_same` instead of null. The dense dictionary-index path wrote nulls only into the reader's read-range bitmap. It then relied on `returnReaderNulls_` to hand that bitmap back from `resultNulls()`. `setReturnNullsMode` clears that flag whenever `useBulkPath()` is false, and `process::hasAvx2()` makes that permanent off AVX2. `resultNulls()` then returns the output-indexed buffer instead, which nothing on this path filled. It now copies the read-range nulls into that buffer, the way the sparse row-set path already did. Reviewed By: vandreykiv Differential Revision: D116833280
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…ubator#18621) Summary: Reading a Nimble string column that keeps its dictionary encoding dropped every null on any platform where `process::hasAvx2()` is false, which is all of aarch64. A 200-row column holding `always_the_same` with a null every 7th row came back as a `DictionaryVector` carrying no null flags, so row 0 read as `always_the_same` instead of null. The dense dictionary-index path wrote nulls only into the reader's read-range bitmap. It then relied on `returnReaderNulls_` to hand that bitmap back from `resultNulls()`. `setReturnNullsMode` clears that flag whenever `useBulkPath()` is false, and `process::hasAvx2()` makes that permanent off AVX2. `resultNulls()` then returns the output-indexed buffer instead, which nothing on this path filled. It now copies the read-range nulls into that buffer, the way the sparse row-set path already did. Reviewed By: vandreykiv Differential Revision: D116833280
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Summary:
Reading a Nimble string column that keeps its dictionary encoding dropped every null on any platform where
process::hasAvx2()is false, which is all of aarch64. A 200-row column holdingalways_the_samewith a null every 7th row came back as aDictionaryVectorcarrying no null flags, so row 0 read asalways_the_sameinstead of null.The dense dictionary-index path wrote nulls only into the reader's read-range bitmap. It then relied on
returnReaderNulls_to hand that bitmap back fromresultNulls().setReturnNullsModeclears that flag wheneveruseBulkPath()is false, andprocess::hasAvx2()makes that permanent off AVX2.resultNulls()then returns the output-indexed buffer instead, which nothing on this path filled. It now copies the read-range nulls into that buffer, the way the sparse row-set path already did.Reviewed By: vandreykiv
Differential Revision: D116833280