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zstd error when trying to read file produced by Polars #173

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Description

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Polars Python code

import polars as pl

df = pl.DataFrame({
    'DateTime': [
        '2018-02-01 00:00:00', '2018-02-02 00:00:00',
        '2018-02-03 00:00:00', '2018-02-04 00:00:00',
        '2018-02-05 00:00:00'
    ],
    'String': ['a', 'b', 'c', 'd', 'e'],
    'Float': [1.2, 3.4, 5.6, 7.8, 9.0],
}).select(
    pl.col('DateTime').str.strptime(pl.Datetime, '%Y-%m-%d %H:%M:%S'),
    pl.exclude('DateTime')
)

print(df)
df.write_parquet("test.parquet", compression='zstd')

Note that compression='zstd' is the default.

Generated Parquet file: test.parquet.zip.

Parquet.jl code

import Pkg
Pkg.activate(temp=true)
Pkg.add([
    Pkg.PackageSpec(name="Parquet", version="0.8.4"),
    Pkg.PackageSpec(name="DataFrames", version="1.5.0")
])
Pkg.status()

import Parquet
Parquet.read_parquet("test.parquet") |> DataFrame

Parquet.jl error

ERROR: zstd error
Stacktrace:
  [1] changemode!(stream::TranscodingStreams.TranscodingStream{CodecZstd.ZstdDecompressor, IOBuffer}, newmode::Symbol)
    @ TranscodingStreams ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:742
  [2] callprocess(stream::TranscodingStreams.TranscodingStream{CodecZstd.ZstdDecompressor, IOBuffer}, inbuf::TranscodingStreams.Buffer, outbuf::TranscodingStreams.Buffer)
    @ TranscodingStreams ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:668
  [3] fillbuffer(stream::TranscodingStreams.TranscodingStream{CodecZstd.ZstdDecompressor, IOBuffer}; eager::Bool)
    @ TranscodingStreams ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:596
  [4] fillbuffer
    @ ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:582 [inlined]
  [5] eof
    @ ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:201 [inlined]
  [6] readbytes!(stream::TranscodingStreams.TranscodingStream{CodecZstd.ZstdDecompressor, IOBuffer}, b::Vector{UInt8}, nb::Int64)
    @ TranscodingStreams ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:387
  [7] readbytes!
    @ ~/.julia/packages/TranscodingStreams/MQucZ/src/stream.jl:384 [inlined]
  [8] (::Parquet.var"#46#47"{Parquet.ColumnChunkPages, Int64})()
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/reader.jl:187
  [9] (::Parquet.var"#40#42"{Parquet.var"#46#47"{Parquet.ColumnChunkPages, Int64}, Parquet.PageLRU, Tuple{Parquet.PAR2.ColumnChunk, Int64}})()
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/reader.jl:34
 [10] lock(f::Parquet.var"#40#42"{Parquet.var"#46#47"{Parquet.ColumnChunkPages, Int64}, Parquet.PageLRU, Tuple{Parquet.PAR2.ColumnChunk, Int64}}, l::ReentrantLock)
    @ Base ./lock.jl:229
 [11] cacheget
    @ ~/.julia/packages/Parquet/6tj1X/src/reader.jl:30 [inlined]
 [12] iterate(ccp::Parquet.ColumnChunkPages, startpos::Int64)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/reader.jl:167
 [13] iterate(ccpv::Parquet.ColumnChunkPageValues{Int64}, startpos::Int64)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/reader.jl:262
 [14] iterate
    @ ~/.julia/packages/Parquet/6tj1X/src/reader.jl:240 [inlined]
 [15] setrow(cursor::Parquet.ColCursor{Int64}, row::Int64)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/cursor.jl:114
 [16] Parquet.ColCursor(par::Parquet.File, colname::Vector{String}; rows::UnitRange{Int64}, row::Int64)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/cursor.jl:62
 [17] ColCursor
    @ ~/.julia/packages/Parquet/6tj1X/src/cursor.jl:56 [inlined]
 [18] #59
    @ ./none:0 [inlined]
 [19] iterate
    @ ./generator.jl:47 [inlined]
 [20] collect(itr::Base.Generator{Vector{Vector{String}}, Parquet.var"#59#61"{UnitRange{Int64}, Parquet.File}})
    @ Base ./array.jl:782
 [21] Parquet.BatchedColumnsCursor(par::Parquet.File; rows::UnitRange{Int64}, batchsize::Int64, reusebuffer::Bool, use_threads::Bool)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/cursor.jl:254
 [22] cursor(table::Parquet.Table)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/simple_reader.jl:130
 [23] load(table::Parquet.Table)
    @ Parquet ~/.julia/packages/Parquet/6tj1X/src/simple_reader.jl:134
 [24] getcolumn
    @ ~/.julia/packages/Parquet/6tj1X/src/simple_reader.jl:186 [inlined]
 [25] getcolumn
    @ ~/.julia/packages/Parquet/6tj1X/src/simple_reader.jl:184 [inlined]
 [26] fromcolumns(x::Parquet.Table, names::Vector{Symbol}; copycols::Bool)
    @ DataFrames ~/.julia/packages/DataFrames/LteEl/src/other/tables.jl:36
 [27] fromcolumns
    @ ~/.julia/packages/DataFrames/LteEl/src/other/tables.jl:36 [inlined]
 [28] #fromcolumns#879
    @ ~/.julia/packages/DataFrames/LteEl/src/other/tables.jl:45 [inlined]
 [29] DataFrame(x::Parquet.Table; copycols::Nothing)
    @ DataFrames ~/.julia/packages/DataFrames/LteEl/src/other/tables.jl:59
 [30] DataFrame
    @ ~/.julia/packages/DataFrames/LteEl/src/other/tables.jl:48 [inlined]
 [31] |>(x::Parquet.Table, f::Type{DataFrame})
    @ Base ./operators.jl:907
 [32] top-level scope
    @ REPL[11]:1

Versions

  • Parquet v0.8.4
  • DataFrames v1.5.0
julia> versioninfo()
Julia Version 1.9.0-rc2
Commit 72aec423c2a (2023-04-01 10:41 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin21.4.0)
  CPU: 4 × Intel(R) Core(TM) i5-3330S CPU @ 2.70GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-14.0.6 (ORCJIT, ivybridge)
  Threads: 1 on 4 virtual cores

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