Exporting data to Azure Blob Storage may inadvertently overwrite an existing file with the same name
Details
| Detail name | Value |
|---|---|
| Changelog Number | 29054 |
| Type | Bug |
| Status | Resolved |
| Affected Versions | Exasol 2025.1.5, Exasol 2025.2.0, Exasol 2026.1.0 |
| Fix Versions | Exasol 2026.1.0, Exasol 2025.2.1, Exasol 2025.1.10 |
| Resolution Date | 2026-02-18 |
Description
Exporting data to Azure Blob Storage may inadvertently, and without warning, overwrite an existing file with the same name.
Details
When exporting data to Azure Blob Storage, the default behavior is to append the new data to a file, if a file with the same name already exists in the specified Azure Blob Storage container. If such a file does not already exist, it will be created.
However, it can happen that the check for an existing file is not performed correctly, and an existing file is not detected. In this case, Exasol will not attempt to append the data to an existing file, but rather create a file as new which overwrites any previous file.
Workaround
Unfortunately, there is not a workaround for this other than to avoid using names for files which already exist in the specified Azure Blob Storage container.
Fix
The issue has been fixed such that existing files will be recognizes as such. Thus, overwriting an existing file will not happen by default.
