Deduplicate project_group_links records
What does this MR do and why?
The project_group_links table should only contain unique pairs of group_id and project_id. This commit deduplicates the current records to prepare for adding a unique index on (group_id, project_id).
This change ensures data integrity by eliminating duplicate relationships between groups and projects.
References
Query plans
- https://console.postgres.ai/gitlab/gitlab-production-main/sessions/39508/commands/121553
- https://console.postgres.ai/gitlab/gitlab-production-main/sessions/39508/commands/121491
How to set up and validate locally
Run bin/rails db:migrate.
MR acceptance checklist
Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.
Related to #535122 (closed)