diff --git a/brmbar3/brmbar/Shop.py b/brmbar3/brmbar/Shop.py
index 0f672c2..85251de 100644
--- a/brmbar3/brmbar/Shop.py
+++ b/brmbar3/brmbar/Shop.py
@@ -100,10 +100,16 @@ class Shop:
         #self.db.commit()
 
     def withdraw_credit(self, credit, user):
-        transaction = self._transaction(responsible = user, description = "BrmBar credit withdrawal for " + user.name)
-        self.cash.credit(transaction, credit, user.name)
-        user.debit(transaction, credit, "Credit withdrawal")
+        trn = self.db.execute_and_fetch(
+            "SELECT public.withdraw_credit(%s,  %s, %s, %s)",
+            [self.cash.id, credit, user.id, user.name]
+        )[0]
         self.db.commit()
+        return trn # unused
+        #transaction = self._transaction(responsible = user, description = "BrmBar credit withdrawal for " + user.name)
+        #self.cash.credit(transaction, credit, user.name)
+        #user.debit(transaction, credit, "Credit withdrawal")
+        #self.db.commit()
 
     def transfer_credit(self, userfrom, userto, amount):
         self.add_credit(amount, userto)
diff --git a/brmbar3/schema/0013-shop-withdraw-credit.sql b/brmbar3/schema/0013-shop-withdraw-credit.sql
new file mode 100644
index 0000000..94ad9b2
--- /dev/null
+++ b/brmbar3/schema/0013-shop-withdraw-credit.sql
@@ -0,0 +1,64 @@
+--
+-- 0012-shop-add-credit.sql
+--
+-- #12 - stored function for cash withdrawal transactions
+--
+-- ISC License
+--
+-- Copyright 2023-2025 Brmlab, z.s.
+-- TMA <tma+hs@jikos.cz>
+--
+-- Permission to use, copy, modify, and/or distribute this software
+-- for any purpose with or without fee is hereby granted, provided
+-- that the above copyright notice and this permission notice appear
+-- in all copies.
+--
+-- THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+-- WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+-- WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+-- AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+-- CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+-- OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+-- NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+-- CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+--
+
+-- To require fully-qualified names
+SELECT pg_catalog.set_config('search_path', '', false);
+
+DO $upgrade_block$
+BEGIN
+
+IF brmbar_privileged.has_exact_schema_version(12) THEN
+
+CREATE OR REPLACE FUNCTION public.withdraw_credit(
+	i_cash_account_id public.accounts.id%TYPE,
+	i_credit NUMERIC,
+	i_user_id public.accounts.id%TYPE,
+	i_user_name TEXT
+) RETURNS VOID
+LANGUAGE plpgsql
+AS $$
+DECLARE
+	v_transaction_id public.transactions.id%TYPE;
+BEGIN
+	-- Create a new transaction
+	v_transaction_id := brmbar_privileged.create_transaction(i_user_id, 'BrmBar credit withdrawal for ' || i_user_name);
+	-- Debit cash (credit replenishment)
+	INSERT INTO public.transaction_splits (transaction, side, account, amount, memo)
+	VALUES (v_transaction_id, 'credit', i_cash_account_id, i_credit, i_user_name);
+	-- Credit the user
+	INSERT INTO public.transaction_splits (transaction, side, account, amount, memo)
+	VALUES (v_transaction_id, 'debit', i_user_id, i_credit, 'Credit withdrawal');
+END;
+$$;
+
+
+
+PERFORM brmbar_privileged.upgrade_schema_version_to(13);
+END IF;
+
+END;
+$upgrade_block$;
+
+-- vim: set ft=plsql :