Initial commit

migrations/triggers_hospital_discharge.sql

@@ -0,0 +1,55 @@
+-- Проверка: выписка должна быть позже поступления
+CREATE OR REPLACE FUNCTION check_discharge_after_admission ()
+    RETURNS TRIGGER
+    AS $$
+DECLARE
+    admission_time timestamp;
+BEGIN
+    SELECT
+        admission_datetime INTO admission_time
+    FROM
+        hospital_admission
+    WHERE
+        hospital_admission_id = NEW.hospital_admission_id;
+    IF NEW.discharge_datetime <= admission_time THEN
+        RAISE EXCEPTION
+            USING ERRCODE = 'P0001', MESSAGE = '10003: DISCHARGE_BEFORE_ADMISSION';
+        END IF;
+        RETURN NEW;
+END;
+$$
+LANGUAGE plpgsql;
+
+CREATE TRIGGER trg_check_discharge_after_admission
+    BEFORE INSERT OR UPDATE ON hospital_discharge
+    FOR EACH ROW
+    EXECUTE FUNCTION check_discharge_after_admission ();
+
+-- Триггер: нельзя создать выписку, если уже есть выписка по этой госпитализации
+CREATE OR REPLACE FUNCTION check_unique_discharge ()
+    RETURNS TRIGGER
+    AS $$
+DECLARE
+    discharge_count integer;
+BEGIN
+    SELECT
+        COUNT(*) INTO discharge_count
+    FROM
+        hospital_discharge
+    WHERE
+        hospital_admission_id = NEW.hospital_admission_id
+        AND hospital_discharge_id <> COALESCE(NEW.hospital_discharge_id, -1);
+    IF discharge_count > 0 THEN
+        RAISE EXCEPTION
+            USING ERRCODE = 'P0001', MESSAGE = '10004: DISCHARGE_ALREADY_EXISTS';
+        END IF;
+        RETURN NEW;
+END;
+$$
+LANGUAGE plpgsql;
+
+CREATE TRIGGER trg_check_unique_discharge
+    BEFORE INSERT OR UPDATE ON hospital_discharge
+    FOR EACH ROW
+    EXECUTE FUNCTION check_unique_discharge ();
+