Add update_person procedure with validation for unique name and email

database.sql

@@ -13,7 +13,7 @@ CREATE OR REPLACE TABLE lang (
 
 CREATE OR REPLACE TABLE person (
     person_id INT AUTO_INCREMENT PRIMARY KEY,
-    person_name VARCHAR(100),
+    person_name VARCHAR(100) UNIQUE,
     email VARCHAR(100) UNIQUE,
     hashed_password VARCHAR(100),
     salt BINARY(16),

procedures/update/person.sql

@@ -0,0 +1,58 @@
+-- Use the database
+USE smartcooking;
+
+DELIMITER //
+
+CREATE OR REPLACE PROCEDURE update_person(
+    IN p_person_id INT,
+    IN p_name VARCHAR(100),
+    IN p_email VARCHAR(100),
+    IN p_hashed_password VARBINARY(255),
+    IN p_salt BINARY(16),
+    IN p_language_iso_code CHAR(2)
+)
+BEGIN
+    DECLARE name_exists INT;
+    DECLARE email_exists INT;
+    DECLARE v_language_id INT;
+
+    -- Check if the person name or email already exists
+    SELECT
+        SUM(person_name = p_name AND person_id != p_person_id),
+        SUM(email = p_email AND person_id != p_person_id)
+    INTO name_exists, email_exists
+    FROM person;
+
+    IF name_exists > 0 THEN
+        SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'User name already exists for another record';
+    END IF;
+
+    IF email_exists > 0 THEN
+        SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'Email already exists for another record';
+    END IF;
+
+    -- Retrieve the language ID if provided
+    IF p_language_iso_code IS NOT NULL THEN
+        SELECT language_id INTO v_language_id
+        FROM lang
+        WHERE iso_code = p_language_iso_code;
+
+        IF v_language_id IS NULL THEN
+            SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'Invalid language code';
+        END IF;
+    ELSE
+        SET v_language_id = NULL;
+    END IF;
+
+    -- Update the person record
+    UPDATE person
+    SET
+        person_name = COALESCE(p_name, person_name),
+        email = COALESCE(p_email, email),
+        hashed_password = COALESCE(p_hashed_password, hashed_password),
+        salt = COALESCE(p_salt, salt),
+        language_id = COALESCE(v_language_id, language_id)
+    WHERE person_id = p_person_id;
+END //
+
+DELIMITER ;