18.8.4 to 18.9.0 EE upgrade error PG::CheckViolation on "gpg_key_subkeys"
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Upgrading from 18.8.4 to 18.9.0 or a self managed EE installation the following output was encountered:
```
["gpg_key_subkeys"](/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:129:in `run_block_with_lock_timeout'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:97:in `run'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/lock_retry_mixin.rb:44:in `ddl_transaction'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/runner_backoff/active_record_mixin.rb:21:in `execute_migr ation_in_transaction'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/pg_backend_pid.rb:14:in `with_advisory_lock'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:226:in `configure_database'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:182:in `configure_pg_databases'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:114:in `block (3 levels) in <top (required)>'
/opt/gitlab/embedded/bin/bundle:25:in `<main>'
Caused by:
PG::CheckViolation: ERROR: check constraint "check_f6590fe2c1" of relation "gpg_key_subkeys" is violated by some row
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/constraints_helpers.rb:122:in `block in validate_check_co nstraint'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/timeout_helpers.rb:31:in `disable_statement_timeout'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/constraints_helpers.rb:119:in `validate_check_constraint'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/constraints_helpers.rb:235:in `validate_not_null_constrai nt'
/opt/gitlab/embedded/service/gitlab-rails/db/post_migrate/20260114160300_validate_not_null_constraint_on_gpg_key_subkeys_user_id.r b:9:in `up'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migration_helpers/restrict_gitlab_schema.rb:33:in `block in exec_mig ration'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/query_analyzer.rb:94:in `within'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migration_helpers/restrict_gitlab_schema.rb:30:in `exec_migration'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migration_helpers/automatic_lock_writes_on_tables.rb:21:in `exec_mig ration'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migration_helpers/require_disable_ddl_transaction_for_multiple_locks .rb:71:in `exec_migration'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:123:in `run_block'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:134:in `block in run_block_with_lock_timeout'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:127:in `public_send'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:127:in `block in write_using_load _balancer'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/load_balancer.rb:141:in `block in read_write'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/load_balancer.rb:229:in `retry_with_backoff'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/load_balancer.rb:131:in `read_write'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:126:in `write_using_load_balancer '
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/load_balancing/connection_proxy.rb:78:in `transaction'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:129:in `run_block_with_lock_timeout'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/with_lock_retries.rb:97:in `run'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/lock_retry_mixin.rb:44:in `ddl_transaction'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/runner_backoff/active_record_mixin.rb:21:in `execute_migr ation_in_transaction'
/opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/database/migrations/pg_backend_pid.rb:14:in `with_advisory_lock'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:226:in `configure_database'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:182:in `configure_pg_databases'
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:114:in `block (3 levels) in <top (required)>'
/opt/gitlab/embedded/bin/bundle:25:in `<main>'
Tasks: TOP => db:migrate
(See full trace by running task with --trace)
STDERR:
---- End output of "bash" ----
Ran "bash" returned 1
===
There was an error running gitlab-ctl reconfigure. Please check the output above for more
details.
===)
```
issue