Refactor code structure for improved readability and maintainability

sql/diagnotics/diagnostics.sql

@@ -61,16 +61,21 @@ LIMIT 10;
 \echo '3. TABLE SIZES (Top 10)'
 \echo '-----------------------------------------'
 
-SELECT 
+SELECT
     s.schemaname,
-    s.relname as tablename,
-    pg_size_pretty(pg_total_relation_size(s.schemaname||'.'||s.relname)) AS total_size,
-    pg_size_pretty(pg_relation_size(s.schemaname||'.'||s.relname)) AS table_size,
-    pg_size_pretty(pg_total_relation_size(s.schemaname||'.'||s.relname) - pg_relation_size(s.schemaname||'.'||s.relname)) AS index_size,
-    s.n_live_tup as row_count
-FROM pg_stat_user_tables s
+    s.relname AS tablename,
+    pg_size_pretty(pg_total_relation_size(fqname)) AS total_size,
+    pg_size_pretty(pg_relation_size(fqname)) AS table_size,
+    pg_size_pretty(pg_total_relation_size(fqname) - pg_relation_size(fqname)) AS index_size,
+    s.n_live_tup AS row_count
+FROM (
+    SELECT
+        s.*,
+        quote_ident(s.schemaname) || '.' || quote_ident(s.relname) AS fqname
+    FROM pg_stat_user_tables s
+) s
 WHERE s.schemaname IN ('library', 'users', 'authentication', 'displaypreferences', 'activitylog')
-ORDER BY pg_total_relation_size(s.schemaname||'.'||s.relname) DESC
+ORDER BY pg_total_relation_size(fqname) DESC
 LIMIT 10;
 
 \echo ''
@@ -200,8 +205,8 @@ FROM pg_stat_user_indexes
 WHERE schemaname IN ('library', 'users', 'authentication', 'displaypreferences', 'activitylog')
   AND idx_scan < 50
   AND pg_relation_size(indexrelid) > 1000000
-ORDER BY pg_relation_size(indexrelid) DESC
-LIMIT 10;
+ORDER BY tablename, pg_relation_size(indexrelid) DESC;
+--LIMIT 10;
 
 \echo ''
 
@@ -341,7 +346,7 @@ BEGIN
     FROM pg_stat_database WHERE datname = 'jellyfin';
     
     IF hit_ratio < 95 THEN
-        RAISE WARNING 'Low cache hit ratio: %%. Target: >95%%', hit_ratio;
+        RAISE WARNING 'Low cache hit ratio: %. Target: >95%%', hit_ratio;
         RAISE NOTICE 'RECOMMENDATION: Increase shared_buffers and effective_cache_size';
     END IF;