From cfaa7eb095514997ca9033c1164ff0091b0322dc Mon Sep 17 00:00:00 2001
From: Luca <102960244+Luca-Timo@users.noreply.github.com>
Date: Sat, 30 May 2026 21:10:10 +0200
Subject: [PATCH] fix(restore): re-sync PostgreSQL sequences after psql load
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pg_dump emits setval() statements for SERIAL/IDENTITY columns, but
they don't always land cleanly: --clean ordering, knex pool sequence
caching, rows inserted mid-restore (the pre-restore safety backup
writes a database_backup_runs row before DROP), etc. Net result on
Ralf's install after a successful restore:

  - "A record with this value already exists" on every CRUD action
  - duplicate key value violates unique constraint
    "database_backup_runs_pkey" on the next Run Backup Now

Same root cause: every SERIAL column's sequence was pointing at or
below MAX(id), so the next INSERT collided.

Fix: append a DO block after the psql restore that walks pg_class +
pg_attribute and setval()s every public-schema sequence to
GREATEST(MAX(<col>), 1). Cheap (a few ms even on large schemas),
safe (read-only on row data), idempotent — re-running it just
re-asserts the same values.

Seventh latent PG-restore bug discovered on Ralf's install tonight.
Manual hand-fix worked; this commit makes the fix automatic for
every future restore.
---
 backend/src/services/restoreService.js | 46 ++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/backend/src/services/restoreService.js b/backend/src/services/restoreService.js
index 1ea6c702..a17ecc52 100644
--- a/backend/src/services/restoreService.js
+++ b/backend/src/services/restoreService.js
@@ -906,6 +906,52 @@ class RestoreService {
 
         // Restore from backup — this one DOES connect to the target DB.
         await spawnFromFile('psql', ['-h', host, '-p', String(port), '-U', user, '-d', database], restoreFile, { env });
+
+        // Re-sync every SERIAL / IDENTITY sequence in the public schema
+        // to MAX(id)+1 of its owning table. pg_dump emits setval()
+        // statements, but they don't always land cleanly when:
+        //   - the dump has `--clean` (the setval may execute before
+        //     the rebuilt rows, depending on dump ordering)
+        //   - the in-process knex pool had a cached sequence value
+        //     before db.destroy() (already mitigated, but defensive)
+        //   - rows were inserted mid-restore (the pre-restore safety
+        //     backup creates a database_backup_runs row before DROP)
+        // Result if skipped: every subsequent INSERT into a serial-id
+        // table fails with `duplicate key value violates unique
+        // constraint "<table>_pkey"`. Surfaced on Ralf's install as
+        // "A record with this value already exists" on every CRUD
+        // action AND `database_backup_runs_pkey` violation on the
+        // next Run Backup Now. Fix is a single DO block that walks
+        // pg_class + pg_attribute and setval()s each sequence to
+        // GREATEST(MAX(<col>), 1). Cheap (a few ms even on large
+        // schemas), safe (doesn't touch row data), idempotent.
+        this.log('info', 'Re-syncing PostgreSQL sequences to MAX(id) of each table...');
+        await spawnAsync('psql', [
+          '-h', host, '-p', String(port), '-U', user, '-d', database,
+          '-c',
+          `DO $$
+DECLARE
+  r RECORD;
+  max_id BIGINT;
+BEGIN
+  FOR r IN
+    SELECT n.nspname AS schema_name, t.relname AS table_name, a.attname AS column_name,
+           pg_get_serial_sequence(quote_ident(n.nspname) || '.' || quote_ident(t.relname), a.attname) AS seq_name
+    FROM pg_class t
+    JOIN pg_namespace n ON n.oid = t.relnamespace
+    JOIN pg_attribute a ON a.attrelid = t.oid
+    WHERE n.nspname = 'public'
+      AND t.relkind = 'r'
+      AND a.attnum > 0
+      AND NOT a.attisdropped
+      AND pg_get_serial_sequence(quote_ident(n.nspname) || '.' || quote_ident(t.relname), a.attname) IS NOT NULL
+  LOOP
+    EXECUTE format('SELECT COALESCE(MAX(%I), 0) FROM %I.%I', r.column_name, r.schema_name, r.table_name) INTO max_id;
+    EXECUTE format('SELECT setval(%L, %s, true)', r.seq_name, GREATEST(max_id, 1));
+  END LOOP;
+END $$;`
+        ], { env });
+        this.log('info', 'Sequence resync completed');
       }
 
       // Re-initialize database connection