Re:Summing columns in remote Parquet files using DuckDB
by ies7 on Thursday November 16, 2023 @09:09PM
(#38298425)
TIL. Usually I just went with SELECT * FROM 'folder/prefix*.parquet'
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Re:Summing columns in remote Parquet files using DuckDB
by simonw on Thursday November 16, 2023 @09:41PM
(#38298700)
That works for files on disk but not for files fetched via HTTP - though apparently DuckDB can do that for some situations, eg if they are in an S3 bucket that it can list files in.
Re:Summing columns in remote Parquet files using DuckDB
by pests on Thursday November 16, 2023 @10:24PM
(#38299092)
Yep - HTTP has no native support for file listings. In the old days it would be served at the index of a url path if no actual file was available - but that was always a feature of the http server and not anything unique to HTTP. Protocols like S3 and FTP have listings built in.
Re:Summing columns in remote Parquet files using DuckDB
by booi on Friday November 17, 2023 @12:55AM
(#38300079)
HTTP doesn't but I think you can in WebDAV, HTTP's long lost "file management" extension which actually has great support from most HTTP servers
Re:Summing columns in remote Parquet files using DuckDB
by chrisjc on Friday November 17, 2023 @01:50AM
(#38300372)
Actually...
(sorry, not picking on you Simon! Awesome post and I just love reading and talking about this stuff)
With duckdb running on python you can register your own file-system adapters. This means that you can do things like intercept globbing, transform urls/path or physically getting files.
This means that you could inject whatever listing/lookup that might be needed for your read_{format}() table function use case.
http://duckdb.org/docs/guides/python/filesystems
However, it is true that there is no standard way to glob over HTTP unless you're using something like S3.
Re:Summing columns in remote Parquet files using DuckDB
by ies7 on Friday November 17, 2023 @08:14AM
(#38303025)
Yeah my bad. I only used it with S3 and somehow my brain think http will be the same.
Re:Summing columns in remote Parquet files using DuckDB
by BohuTANG on Monday November 20, 2023 @09:29PM
(#38358198)
For http(s) remote file, we can support glob pattern, for example:
https://<thehfurl>/resolve/main/data/0000[00-55].parquet'
Databend supports this pattern: https://databend.rs/doc/load-data/load/http#loading-with-glo...