fix: automatic column additions, permissions grants and docs updates for seamless upgrades

postgresql/procedures/02_enable_partitioning.sql

@@ -74,11 +74,24 @@ BEGIN
 END $$;
 
 -- ==========================================================================
--- IMPORTANT: If the Zabbix Server connects with a non-superuser (e.g., 'zabbix'),
--- that user MUST have access to the partitions schema for the housekeeper trigger
--- to work. Without these GRANTs, every INSERT into housekeeper will FAIL.
--- Uncomment and adjust the username below:
+-- IMPORTANT: To ensure the Zabbix Server can insert into the housekeeper
+-- table without permission issues, we automatically grant access to the 
+-- partitions schema to the owner of the housekeeper table.
 -- ==========================================================================
--- GRANT USAGE ON SCHEMA partitions TO zabbix;
--- GRANT SELECT ON partitions.config TO zabbix;
+DO $$
+DECLARE
+    v_owner text;
+BEGIN
+    SELECT pg_get_userbyid(c.relowner) INTO v_owner
+    FROM pg_class c
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    WHERE c.relname = 'housekeeper' AND pg_table_is_visible(c.oid);
 
+    IF v_owner IS NOT NULL THEN
+        EXECUTE format('GRANT USAGE ON SCHEMA partitions TO %I', v_owner);
+        EXECUTE format('GRANT SELECT ON partitions.config TO %I', v_owner);
+        RAISE NOTICE 'Granted partitions schema permissions to housekeeper owner: %', v_owner;
+    ELSE
+        RAISE WARNING 'housekeeper table not found, could not grant permissions automatically!';
+    END IF;
+END $$;