Preliminary checklist

• I am using the latest stable version of DDEV (see upgrade guide)
• I have searched existing issues
• I have checked the troubleshooting guide
• I have run ddev utility test or at least ddev utility diagnose to include output below

Output of ddev utility test or ddev utility diagnose

DDEV Diagnostic Report
======================

Environment
===========
ℹ DDEV version: v1.25.1
ℹ OS: Linux x86_64
ℹ Distro: Ubuntu 24.04.2 LTS
ℹ Shell: /usr/bin/zsh
ℹ Docker provider: linux-docker
ℹ Docker version: 28.3.2

Docker Environment
==================
✓ Docker is running
✓ Docker disk space: 66% used
✓ Can run containers with volume mounts
✓ Internet access from containers
✓ Docker buildx working
✓ Docker authentication configured

Network Connectivity
====================
✓ Internet accessible from host
✓ DNS resolves *.ddev.site

HTTPS/mkcert
============
✓ mkcert is installed: v1.4.4
✓ mkcert CA certificates exist

Current Project
===============
ℹ Name: my-project
ℹ Type: drupal10
ℹ Status: running
✓ No custom configurations detected
ℹ Installed add-ons (2):
ℹ   - memcached
ℹ   - solr
✓ Project containers are responsive

Expected Behavior

ddev import-db should import the dump successfully. The same dump imports correctly when run directly through the MySQL client, and the table-level collation allows the relevant values to coexist.

Actual Behavior

On DDEV v1.25.1, ddev import-db fails with a duplicate key error during import.

Example error:

ERROR 1062 (23000) at line 28442: Duplicate entry '/ecosse/edimbourg -fr' for key 'redirect_404.PRIMARY'

The dump contains both of these values in redirect_404:
('/ecosse/edimbourg','fr',143,0,1771945569,0),
('/ecosse/edimbourg ','fr',39,0,1766907536,0),

Importing the exact same dump directly with:
ddev mysql db < dump.sql

Steps To Reproduce

Steps To Reproduce

1. Use DDEV v1.25.1.
2. Start a project using MySQL 8.0.
3. Use a dump containing a table created with utf8mb4_0900_ai_ci.
4. Ensure that table contains rows that differ only by trailing whitespace in a PK/unique key, for example:

   ('/ecosse/edimbourg','fr',...)
   ('/ecosse/edimbourg ','fr',...)

5. Run: ddev import-db --file=dump.sql.gz
   6.Observe the duplicate key import failure.
   7.Import the same dump with: gzip -cd dump.sql.gz | ddev mysql db
6. Observe that the direct MySQL import succeeds.

Anything else?

Anything else?

This started reproducing for us after updating from DDEV v1.24.4 to v1.25.1.

A likely related change in the DDEV release notes is:
fix(import-db): replace modern collations with server default

This appears to affect dumps where modern collations such as utf8mb4_0900_ai_ci are important to keep values distinct during import.

We’ve also seen a similar failure on another project with a different unique key (users_field_data.user_name), where the underlying cause was trailing spaces in the stored value. That suggests this is not isolated to a single table or codebase, but may affect any dump where values remain distinct under the original collation and then collide during ddev import-db.