Ensure NOT NULL constraints in SQL tables

Refactor SQL table creation scripts to add NOT NULL constraints where necessary. This change ensures data integrity by preventing null values in critical columns across the 'verify_form', 'form', 'rate_limit', and 'form_active' tables.

src/main/java/com/alttd/forms/database/Database.java

@@ -15,36 +15,36 @@ public class Database {
                 // language=SQL
                 """
                 CREATE TABLE IF NOT EXISTS verify_form(
-                    e_mail VARCHAR(256),
-                    verification_code INT,
-                    formId INT,
+                    e_mail VARCHAR(256) NOT NULL,
+                    verification_code INT NOT NULL,
+                    formId INT NOT NULL,
                     PRIMARY KEY(e_mail, verification_code)
                 )
                 """,
                 // language=SQL
                 """
                 CREATE TABLE IF NOT EXISTS form(
-                    formId INT AUTO_INCREMENT,
-                    creation_date BIGINT,
-                    form_json TEXT,
-                    form_class VARCHAR(64),
+                    formId INT AUTO_INCREMENT NOT NULL,
+                    creation_date BIGINT NOT NULL,
+                    form_json TEXT NOT NULL,
+                    form_class VARCHAR(64) NOT NULL,
                     PRIMARY KEY(formId)
                 )
                 """,
                 // language=SQL
                 """
                 CREATE TABLE IF NOT EXISTS rate_limit(
-                    id INT AUTO_INCREMENT,
-                    time TIMESTAMP,
-                    ip VARCHAR(45),
-                    mail VARCHAR(256),
+                    id INT AUTO_INCREMENT NOT NULL,
+                    time TIMESTAMP NOT NULL,
+                    ip VARCHAR(45) NOT NULL,
+                    mail VARCHAR(256) NOT NULL,
                     PRIMARY KEY(id)
                 )
                 """,
                 // language=SQL
                 """
                 CREATE TABLE IF NOT EXISTS form_active(
-                    id INT AUTO_INCREMENT,
+                    id INT AUTO_INCREMENT NOT NULL,
                     name VARCHAR(64) NOT NULL,
                     active_from TIMESTAMP NOT NULL,
                     active_until TIMESTAMP NOT NULL,