account entry reference stuff

schema/changes02.sql

@@ -93,7 +93,21 @@ CREATE OR REPLACE FUNCTION maintain_ledger()
 RETURNS TRIGGER
 LANGUAGE plpgsql
 AS $$
+DECLARE
+  tenant RECORD;
+  adjusted_description text;
 BEGIN
+  IF ((NEW.description = 'Miete') AND (NEW.account_entry_category = 2)) THEN
+    SELECT firstname, lastname
+      INTO tenant
+      FROM tenant_t
+      WHERE account = NEW.account;
+    adjusted_description := 'Miete ' || extract(year from NEW.created_at)::text || ' ' || to_char(to_date(extract(month from NEW.created_at)::text, 'MM'), 'Month') || tenant.firstname || ' ' || tenant.lastname;
+    UPDATE account_entry_t
+      SET description = adjusted_description
+      WHERE id = NEW.id;
+  END IF;
+    
   INSERT INTO account_entry_reference_t (account, account_entry) VALUES (1000, NEW.id);
   RETURN NEW;
 END;