Orphaned table clean up upgrade script

application/src/main/data/upgrade/basic/schema_update.sql

@@ -25,3 +25,89 @@ ALTER TABLE calculated_field ADD COLUMN IF NOT EXISTS additional_info varchar;
 ALTER TABLE rule_chain ADD COLUMN IF NOT EXISTS notes varchar(1000000);
 
 -- RULE CHAIN NOTES MIGRATION END
+
+-- CLEANUP ORPHANED OTA PACKAGE LARGE OBJECTS START
+
+-- This script cleans up orphaned PostgreSQL large objects that are no longer referenced by the ota_package table.
+-- These orphaned objects accumulate when OTA packages are deleted or updated and can consume significant disk space.
+-- Note: only the ota_package.data column uses PostgreSQL large objects (OID type) in ThingsBoard.
+-- This script removes all large objects not referenced by ota_package.data.
+-- If external applications sharing this database also use large objects, their objects WILL be deleted.
+--
+-- This runs as a single transaction, which is acceptable for typical installations (up to tens of thousands
+-- of orphaned objects). For installations with millions of orphaned objects, WAL pressure may be a concern.
+
+DO
+$$
+DECLARE
+    orphan_oid bigint;
+    deleted_count int := 0;
+    failed_count int := 0;
+    total_orphans int;
+    start_ts timestamptz;
+    elapsed_sec numeric;
+BEGIN
+    start_ts := clock_timestamp();
+
+    -- Drop first to ensure fresh data on re-run
+    DROP TABLE IF EXISTS orphan_oids;
+
+    -- Collect orphan OIDs into a temp table to avoid repeating the JOIN each iteration
+    CREATE TEMP TABLE orphan_oids AS
+        SELECT m.oid AS orphan_oid
+        FROM pg_largeobject_metadata m
+        LEFT JOIN ota_package p ON p.data = m.oid
+        WHERE p.data IS NULL;
+
+    SELECT COUNT(*) INTO total_orphans FROM orphan_oids;
+
+    IF total_orphans = 0 THEN
+        RAISE NOTICE 'No orphaned large objects found';
+        DROP TABLE IF EXISTS orphan_oids;
+        RETURN;
+    END IF;
+
+    RAISE NOTICE 'Found % orphaned large objects to clean up', total_orphans;
+
+    FOR orphan_oid IN SELECT o.orphan_oid FROM orphan_oids o
+    LOOP
+        BEGIN
+            PERFORM lo_unlink(orphan_oid);
+            deleted_count := deleted_count + 1;
+
+            IF deleted_count % 1000 = 0 THEN
+                elapsed_sec := EXTRACT(EPOCH FROM clock_timestamp() - start_ts);
+                RAISE NOTICE 'Progress: deleted % of % orphaned large objects (%s elapsed)...',
+                    deleted_count, total_orphans, ROUND(elapsed_sec, 1);
+            END IF;
+        EXCEPTION WHEN OTHERS THEN
+            failed_count := failed_count + 1;
+            RAISE WARNING 'Failed to delete large object with OID %: %', orphan_oid, SQLERRM;
+        END;
+    END LOOP;
+
+    elapsed_sec := EXTRACT(EPOCH FROM clock_timestamp() - start_ts);
+
+    IF failed_count > 0 THEN
+        RAISE NOTICE 'Completed cleanup: deleted %, failed % out of % orphaned large objects (%s elapsed)',
+            deleted_count, failed_count, total_orphans, ROUND(elapsed_sec, 1);
+    ELSE
+        RAISE NOTICE 'Successfully cleaned up all % orphaned large objects (%s elapsed)',
+            deleted_count, ROUND(elapsed_sec, 1);
+    END IF;
+
+    -- Fail the migration if more than 10% of deletions failed, indicating a systemic problem
+    IF failed_count > 0 AND (failed_count::numeric / total_orphans) > 0.1 THEN
+        DROP TABLE IF EXISTS orphan_oids;
+        RAISE EXCEPTION 'OTA cleanup aborted: % of % deletions failed (>10%%), indicating a systemic issue',
+            failed_count, total_orphans;
+    END IF;
+
+    DROP TABLE IF EXISTS orphan_oids;
+EXCEPTION WHEN OTHERS THEN
+    DROP TABLE IF EXISTS orphan_oids;
+    RAISE;
+END;
+$$;
+
+-- CLEANUP ORPHANED OTA PACKAGE LARGE OBJECTS END