Fix deltaLakeAzure url encoded path

[SmitaRKulkarni]

Changelog category (leave one):

• Bug Fix (user-visible misbehavior in an official stable release)

Changelog entry (a user-readable short description of the changes that goes into CHANGELOG.md):

Fix processing of url encoded path in deltaLakeAzure resolves ##103509

Documentation entry for user-facing changes

• Documentation is written (mandatory for new features)

[clickhouse-gh]

Workflow [PR], commit [c167a15]

Summary: ✅

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AI Review

Summary

This PR decodes URI-encoded Delta log file paths before resolving data file locations, fixing DeltaLakeAzure reads for partition directories that contain encoded characters (for example %40). The change is small, focused, and covered by a dedicated integration test that reproduces the encoded-path scenario.

ClickHouse Rules

Item	Status	Notes
Deletion logging	➖
Serialization versioning	➖
Core-area scrutiny	✅
No test removal	✅
Experimental gate	➖
No magic constants	✅
Backward compatibility	✅
SettingsChangesHistory.cpp	➖
PR metadata quality	✅
Safe rollout	✅
Compilation time	✅
No large/binary files	✅

Final Verdict

• Status: ✅ Approve

[clickhouse-gh]

LLVM Coverage Report

Metric	Baseline	Current	Δ
Lines	83.80%	83.80%	+0.00%
Functions	91.10%	91.10%	+0.00%
Branches	76.20%	76.20%	+0.00%

Changed lines: 100.00% (14/14) · Uncovered code

Full report · Diff report

[alexey-milovidov]

Does not look wrong for me, thank you!

[clickgapai]

Hi — this PR may need backporting to 26.3 (LTS), 26.2, 26.1, 25.8 (LTS), but no backport label was found.

Affected code: DeltaLakeMetadataImpl::processMetadataFile and DeltaLakeMetadataImpl::getCheckpointIfExists in DeltaLakeMetadata.cpp — core code present in all supported branches.

Why: User-visible bug fix in DeltaLakeMetadataImpl::processMetadataFile and DeltaLakeMetadataImpl::getCheckpointIfExists. Git log shows DeltaLakeMetadata.cpp predates all supported branches (file existed long before 25.8 release date 2025-08-29). Affected code path is the legacy non-kernel reader, present in every supported branch.

If this should be backported, consider adding pr-must-backport or a version-specific label (e.g. v26.3-must-backport). Ignore this if backporting is not applicable.