[jira] [Commented] (ARROW-17008) Parquet Snappy Compression Fails for Integer Type Data

["Antoine Pitrou (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/ARROW-17008?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17563936#comment-17563936 ] 

Antoine Pitrou commented on ARROW-17008:
----------------------------------------

What are the actual file sizes in each case?

> Parquet Snappy Compression Fails for Integer Type Data
> ------------------------------------------------------
>
>                 Key: ARROW-17008
>                 URL: https://issues.apache.org/jira/browse/ARROW-17008
>             Project: Apache Arrow
>          Issue Type: Bug
>          Components: R
>    Affects Versions: 8.0.0
>         Environment: R4.2.1 Ubuntu 22.04 x86_64
> R4.1.2 Ubuntu 22.04 Aarch64
>            Reporter: Charlie Gao
>            Priority: Major
>
> Snappy compression is not working when writing to parquet for integer type data.
> E.g. compare file sizes for:
> {code:r}
> write_parquet(data.frame(x = 1:1e6), "snappy.parquet", compression = "snappy")
> write_parquet(data.frame(x = 1:1e6), "uncomp.parquet", compression = "uncompressed")
> {code}
> whereas for double:
> {code:r}
> write_parquet(data.frame(x = as.double(1:1e6)), "snappyd.parquet", compression = "snappy")
> write_parquet(data.frame(x = as.double(1:1e6)), "uncompd.parquet", compression = "uncompressed")
> {code}
> I have inspected the integer files using parquet-tools and compression level shows as 0%. Needless to say, I can achieve compression using Spark (sparklyr) etc.
> Thanks.



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