Support reading Iceberg S3 paths with double slashes

[electrum]

Description

Allow reading Iceberg tables written by Glue that have locations containing double slashes. This type of path is not possible to represent by the Hadoop Path object since it normalizes paths, so we can hide the original path in the URI fragment.

Related issues, pull requests, and links

Fixes #11964

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# Iceberg connector
* Allow reading Iceberg tables written by Glue that have locations containing double slashes. ({issue}`11964`)

[electrum]

@rdblue this fixes the issue you encountered

[findepi]

What problem is it solving?
Is it testable?

Allow reading Iceberg tables written by Glue that have locations containing double slashes. This type of path is not possible to represent by the Hadoop Path object since it normalizes paths

thanks for context. What if the normalized path was used later? it should just work, shouldn't it?
or is it about delete deltas not being applied? (cc @alexjo2144)

cc @homar as it may affect vacuuming logic.

[electrum]

This has nothing to do with delete deltas. The issue is that Glue writes S3 key names that contain double slashes, which is perfectly legal for an S3 key, but cannot be transported through an HDFS path.

[electrum]

I don't know a good way to test this, since we can't write such paths with Trino. I don't feel that it's worth the effort to try to construct such a table manually for a test.

[findepi]

S3 key names that contain double slashes, which is perfectly legal for an S3 key, but cannot be transported through an HDFS path.

thanks for clarifying

This has nothing to do with delete deltas.

Sounds like it may or may not be related. Deletion deltas have paths included, so if something was replacing repeated slashes (eg because of going via some intermediate representation), the deletion deltas wouldn't apply.
I hope this is not the case though.
cc @alexjo2144 @homar