diff --git a/aula/schema.sql b/aula/schema.sql
new file mode 100644
index 0000000..9f5bb35
--- /dev/null
+++ b/aula/schema.sql
@@ -0,0 +1,52 @@
+CREATE TABLE IF NOT EXISTS users (
+    user_id SERIAL PRIMARY KEY,
+    first_name varchar(64) NOT NULL,
+    last_name varchar(64) NOT NULL,
+    email varchar(64) NOT NULL,
+    addresse varchar(64) NOT NULL,
+    role varchar(64) NOT NULL CHECK ( role in ('student', 'parent', 'teacher') )
+);
+
+CREATE TABLE IF NOT EXISTS groups (
+    group_id SERIAL PRIMARY KEY,
+    name varchar(64) NOT NULL UNIQUE,
+    leaveable boolean DEFAULT TRUE,
+    parents_can_post boolean DEFAULT FALSE
+);
+
+CREATE TABLE IF NOT EXISTS threads (
+    thread_id SERIAL PRIMARY KEY,
+    title varchar(64) NOT NULL,
+    group_id integer REFERENCES groups(group_id),
+    creator_id integer REFERENCES users(user_id)
+);
+
+CREATE TABLE IF NOT EXISTS messages (
+    message_id SERIAL PRIMARY KEY,
+    content text NOT NULL,
+    thread_id integer REFERENCES threads(thread_id),
+    author_id integer REFERENCES users(user_id),
+    created_date timestamp NOT NULL DEFAULT now()
+);
+
+CREATE TABLE IF NOT EXISTS posts (
+    post_id SERIAL PRIMARY KEY,
+    group_id integer REFERENCES groups(group_id),
+    author_id integer REFERENCES users(user_id),
+    title varchar(64) NOT NULL,
+    content text NOT NULL,
+    created_date timestamp NOT NULL DEFAULT now()
+);
+
+-- Relationships
+CREATE TABLE IF NOT EXISTS users_threads (
+    user_id integer REFERENCES users(user_id),
+    thread_id integer REFERENCES threads(thread_id),
+    PRIMARY KEY (user_id, thread_id)
+);
+
+CREATE TABLE IF NOT EXISTS users_groups (
+    user_id integer REFERENCES users(user_id),
+    group_id integer REFERENCES groups(group_id),
+    PRIMARY KEY (user_id, group_id)
+);
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