From dede3c66deedee4db281cbe490f887328a918a77 Mon Sep 17 00:00:00 2001
From: Andy Atkinson <andyatkinson@gmail.com>
Date: Tue, 26 Mar 2024 21:24:17 -0500
Subject: [PATCH 1/2] Start some triggers

---
 trigger_tests/triggers.sql | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)
 create mode 100644 trigger_tests/triggers.sql

diff --git a/trigger_tests/triggers.sql b/trigger_tests/triggers.sql
new file mode 100644
index 0000000..6e4c281
--- /dev/null
+++ b/trigger_tests/triggers.sql
@@ -0,0 +1,30 @@
+-- https://www.postgresql.org/docs/current/plpgsql-trigger.html
+
+CREATE TABLE employees (
+  id integer,
+  salary integer default 0,
+  updated_at timestamptz
+);
+
+CREATE FUNCTION employee_calc() RETURNS trigger AS $employee_calc$
+    BEGIN
+        -- Check that salary is not null
+        IF NEW.salary IS NULL THEN
+            RAISE EXCEPTION 'salary cannot be null';
+        END IF;
+        IF NEW.salary IS NULL THEN
+            RAISE EXCEPTION '% cannot have null salary', NEW.id;
+        END IF;
+
+        -- Who works for us when they must pay for it?
+        IF NEW.salary < 0 THEN
+            RAISE EXCEPTION '% cannot have a negative salary', NEW.id;
+        END IF;
+
+        NEW.updated_at := current_timestamp;
+        RETURN NEW;
+    END;
+$employee_calc$ LANGUAGE plpgsql;
+
+CREATE TRIGGER employee_calc BEFORE INSERT OR UPDATE ON employees
+    FOR EACH ROW EXECUTE FUNCTION employee_calc();

From 8dafdf0bbc7023d46843030216f9f0f50d799510 Mon Sep 17 00:00:00 2001
From: Andy Atkinson <andyatkinson@gmail.com>
Date: Tue, 26 Mar 2024 22:02:15 -0500
Subject: [PATCH 2/2] Add trigger depth example

---
 trigger_tests/trigger_depth.sql | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 trigger_tests/trigger_depth.sql

diff --git a/trigger_tests/trigger_depth.sql b/trigger_tests/trigger_depth.sql
new file mode 100644
index 0000000..ec58776
--- /dev/null
+++ b/trigger_tests/trigger_depth.sql
@@ -0,0 +1,25 @@
+
+-- https://pgpedia.info/p/pg_trigger_depth.html
+CREATE TABLE foo (id INT, val TEXT);
+
+CREATE OR REPLACE FUNCTION trigger_depth()
+ RETURNS TRIGGER
+ LANGUAGE plpgsql
+AS $$
+ DECLARE
+   depth INT;
+ BEGIN
+   depth := pg_trigger_depth();
+   RAISE NOTICE 'depth: %', depth;
+   IF depth = 1 THEN
+      INSERT INTO foo VALUES(-1, 'test');
+   END IF;
+   RETURN NEW;
+ END;
+$$;
+
+CREATE TRIGGER foo_ins_trigger
+ BEFORE INSERT
+ ON foo
+ FOR EACH ROW
+ EXECUTE FUNCTION trigger_depth();