2 files changed, 13 insertions(+), 4 deletions(-)

M deploy/notify_low_balance.sql
M revert/notify_low_balance.sql

@@ 4,14 4,22 @@
 
 BEGIN;
 
-CREATE OR REPLACE FUNCTION check_and_notify_low_balance() RETURNS TRIGGER AS $$
+CREATE OR REPLACE FUNCTION check_and_notify_low_balance(
+	customerid TEXT
+) RETURNS VOID AS $$
 	DECLARE
 		bal NUMERIC;
 	BEGIN
-		SELECT balance INTO bal FROM balances WHERE customer_id = NEW.customer_id;
+		SELECT balance INTO bal FROM balances WHERE customer_id = customerid;
 		IF bal < 5 THEN
-			SELECT pg_notify('low_balance', NEW.customer_id);
+			PERFORM pg_notify('low_balance', customerid);
 		END IF;
+	END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION check_and_notify_low_balance_trigger() RETURNS TRIGGER AS $$
+	BEGIN
+		PERFORM check_and_notify_low_balance(NEW.customer_id);
 		RETURN NEW;
 	END;
 $$ LANGUAGE plpgsql;


@@ 20,6 28,6 @@ CREATE TRIGGER notify_low_balance
 	AFTER INSERT ON transactions
 	FOR EACH ROW
 	WHEN (NEW.amount < 0)
-	EXECUTE PROCEDURE check_and_notify_low_balance();
+	EXECUTE PROCEDURE check_and_notify_low_balance_trigger();
 
 COMMIT;

@@ 3,6 3,7 @@
 BEGIN;
 
 DROP TRIGGER notify_low_balance ON transactions;
+DROP FUNCTION IF EXISTS check_and_notify_low_balance_trigger;
 DROP FUNCTION check_and_notify_low_balance;
 
 COMMIT;