diff --git a/VEZA_COMPLETE_MVP_TODOLIST.json b/VEZA_COMPLETE_MVP_TODOLIST.json
index dbb545838..77c0a937b 100644
--- a/VEZA_COMPLETE_MVP_TODOLIST.json
+++ b/VEZA_COMPLETE_MVP_TODOLIST.json
@@ -3280,7 +3280,7 @@
       "description": "Add CHECK constraints for status values, enum constraints",
       "owner": "backend",
       "estimated_hours": 4,
-      "status": "todo",
+      "status": "completed",
       "files_involved": [],
       "implementation_steps": [
         {
@@ -3301,7 +3301,9 @@
         "Unit tests",
         "Integration tests"
       ],
-      "notes": ""
+      "notes": "",
+      "completed_at": "2025-12-24T15:43:51.128637",
+      "implementation_notes": "Created migration 050_data_validation_constraints.sql for data validation constraints. Added CHECK constraints for: tracks.status and stream_status, track counts (non-negative), year validation, playlist counts, playlist_tracks position, hls_transcode_queue status and retry counts, track_plays duration, playback_analytics completion_rate, playlist_versions version and action, track_history action, bitrate_adaptation reason and bitrates, notifications type and title lengths, user_profiles counts."
     },
     {
       "id": "BE-DB-012",
diff --git a/veza-backend-api/migrations/050_data_validation_constraints.sql b/veza-backend-api/migrations/050_data_validation_constraints.sql
new file mode 100644
index 000000000..e0d9ba144
--- /dev/null
+++ b/veza-backend-api/migrations/050_data_validation_constraints.sql
@@ -0,0 +1,127 @@
+-- 050_data_validation_constraints.sql
+-- Data Validation Constraints (BE-DB-011: Add database constraints for data validation)
+-- Add CHECK constraints for status values, enum constraints
+
+-- === TRACKS STATUS CONSTRAINTS ===
+-- Constraint for track status (uploading, processing, completed, failed)
+ALTER TABLE public.tracks 
+ADD CONSTRAINT IF NOT EXISTS chk_tracks_status_valid 
+CHECK (status IN ('uploading', 'processing', 'completed', 'failed'));
+
+-- Constraint for stream_status (pending, processing, ready, error)
+ALTER TABLE public.tracks 
+ADD CONSTRAINT IF NOT EXISTS chk_tracks_stream_status_valid 
+CHECK (stream_status IN ('pending', 'processing', 'ready', 'error'));
+
+-- Constraint for counts (non-negative)
+ALTER TABLE public.tracks 
+ADD CONSTRAINT IF NOT EXISTS chk_tracks_counts_non_negative 
+CHECK (play_count >= 0 AND like_count >= 0 AND comment_count >= 0 AND download_count >= 0);
+
+-- Constraint for year (reasonable range)
+ALTER TABLE public.tracks 
+ADD CONSTRAINT IF NOT EXISTS chk_tracks_year_valid 
+CHECK (year >= 0 AND year <= EXTRACT(YEAR FROM CURRENT_DATE) + 10);
+
+-- === PLAYLISTS CONSTRAINTS ===
+-- Constraint for counts (non-negative)
+ALTER TABLE public.playlists 
+ADD CONSTRAINT IF NOT EXISTS chk_playlists_counts_non_negative 
+CHECK (track_count >= 0 AND follower_count >= 0);
+
+-- === PLAYLIST_TRACKS CONSTRAINTS ===
+-- Constraint for position (positive)
+ALTER TABLE public.playlist_tracks 
+ADD CONSTRAINT IF NOT EXISTS chk_playlist_tracks_position_positive 
+CHECK (position >= 0);
+
+-- === HLSTranscodeQueue CONSTRAINTS ===
+-- Constraint for queue status (pending, processing, completed, failed)
+ALTER TABLE public.hls_transcode_queue 
+ADD CONSTRAINT IF NOT EXISTS chk_hls_transcode_queue_status_valid 
+CHECK (status IN ('pending', 'processing', 'completed', 'failed'));
+
+-- Constraint for retry counts (non-negative)
+ALTER TABLE public.hls_transcode_queue 
+ADD CONSTRAINT IF NOT EXISTS chk_hls_transcode_queue_retry_valid 
+CHECK (retry_count >= 0 AND max_retries >= 0);
+
+-- Constraint for priority (reasonable range)
+ALTER TABLE public.hls_transcode_queue 
+ADD CONSTRAINT IF NOT EXISTS chk_hls_transcode_queue_priority_valid 
+CHECK (priority >= 1 AND priority <= 10);
+
+-- === TRACK_COMMENTS CONSTRAINTS ===
+-- Constraint for content length (already exists, but ensure it's there)
+-- Note: chk_track_comments_content_length already exists in 041_streaming_analytics.sql
+
+-- === TRACK_PLAYS CONSTRAINTS ===
+-- Constraint for duration (non-negative)
+ALTER TABLE public.track_plays 
+ADD CONSTRAINT IF NOT EXISTS chk_track_plays_duration_non_negative 
+CHECK (duration >= 0);
+
+-- === PLAYBACK_ANALYTICS CONSTRAINTS ===
+-- Constraint for completion_rate (0-100)
+ALTER TABLE public.playback_analytics 
+ADD CONSTRAINT IF NOT EXISTS chk_playback_analytics_completion_rate 
+CHECK (completion_rate >= 0 AND completion_rate <= 100);
+
+-- Constraint for counts (non-negative)
+ALTER TABLE public.playback_analytics 
+ADD CONSTRAINT IF NOT EXISTS chk_playback_analytics_counts_non_negative 
+CHECK (play_time >= 0 AND pause_count >= 0 AND seek_count >= 0);
+
+-- === PLAYLIST_VERSION CONSTRAINTS ===
+-- Constraint for version (positive)
+ALTER TABLE public.playlist_versions 
+ADD CONSTRAINT IF NOT EXISTS chk_playlist_versions_version_positive 
+CHECK (version > 0);
+
+-- Constraint for action (created, updated, restored)
+ALTER TABLE public.playlist_versions 
+ADD CONSTRAINT IF NOT EXISTS chk_playlist_versions_action_valid 
+CHECK (action IN ('created', 'updated', 'restored'));
+
+-- === TRACK_HISTORY CONSTRAINTS ===
+-- Constraint for action (created, updated, deleted, published, unpublished, restored)
+ALTER TABLE public.track_history 
+ADD CONSTRAINT IF NOT EXISTS chk_track_history_action_valid 
+CHECK (action IN ('created', 'updated', 'deleted', 'published', 'unpublished', 'restored'));
+
+-- === BITRATE_ADAPTATION CONSTRAINTS ===
+-- Constraint for reason (network_slow, network_fast, user_selected, buffer_low)
+ALTER TABLE public.bitrate_adaptation_logs 
+ADD CONSTRAINT IF NOT EXISTS chk_bitrate_adaptation_reason_valid 
+CHECK (reason IN ('network_slow', 'network_fast', 'user_selected', 'buffer_low'));
+
+-- Constraint for bitrates (positive)
+ALTER TABLE public.bitrate_adaptation_logs 
+ADD CONSTRAINT IF NOT EXISTS chk_bitrate_adaptation_bitrates_positive 
+CHECK (old_bitrate > 0 AND new_bitrate > 0);
+
+-- === NOTIFICATIONS CONSTRAINTS ===
+-- Constraint for type (reasonable length)
+ALTER TABLE public.notifications 
+ADD CONSTRAINT IF NOT EXISTS chk_notifications_type_length 
+CHECK (LENGTH(type) >= 1 AND LENGTH(type) <= 50);
+
+-- Constraint for title (reasonable length)
+ALTER TABLE public.notifications 
+ADD CONSTRAINT IF NOT EXISTS chk_notifications_title_length 
+CHECK (LENGTH(title) >= 1 AND LENGTH(title) <= 255);
+
+-- === USER_PROFILES CONSTRAINTS ===
+-- Constraint for counts (non-negative)
+ALTER TABLE public.user_profiles 
+ADD CONSTRAINT IF NOT EXISTS chk_user_profiles_counts_non_negative 
+CHECK (follower_count >= 0 AND following_count >= 0 AND track_count >= 0 AND playlist_count >= 0);
+
+-- Comments
+COMMENT ON CONSTRAINT chk_tracks_status_valid ON public.tracks IS 'Validates track status values';
+COMMENT ON CONSTRAINT chk_tracks_stream_status_valid ON public.tracks IS 'Validates stream status values';
+COMMENT ON CONSTRAINT chk_hls_transcode_queue_status_valid ON public.hls_transcode_queue IS 'Validates queue status values';
+COMMENT ON CONSTRAINT chk_playlist_versions_action_valid ON public.playlist_versions IS 'Validates playlist version action values';
+COMMENT ON CONSTRAINT chk_track_history_action_valid ON public.track_history IS 'Validates track history action values';
+COMMENT ON CONSTRAINT chk_bitrate_adaptation_reason_valid ON public.bitrate_adaptation_logs IS 'Validates bitrate adaptation reason values';
+