chore/trigger tests

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();

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();