feat: Martha's SQL queries for lesson 25 homework

lesson_25/db/db_app/src/main/resources/queries/create_library_users.sql

@@ -0,0 +1,7 @@
+CREATE TABLE library_users (
+    id TEXT PRIMARY KEY,
+    email TEXT UNIQUE NOT NULL,
+    first_name TEXT NOT NULL,
+    last_name TEXT NOT NULL,
+    password TEXT NOT NULL
+);

lesson_25/db/db_app/src/main/resources/queries/marthao.sql

@@ -0,0 +1,29 @@
+SELECT
+    type,
+    COUNT(*) AS item_count
+FROM
+    media_items
+GROUP BY
+   type;
+
+SELECT
+    email,
+    SUM(pages) AS total_pages
+FROM
+    checked_out_items
+JOIN
+    media_items ON checked_out_items.item_id = media_items.id
+GROUP BY
+    email;
+
+//A SELECT query that shows all 5 guests and any corresponding records in the checked_out_items table.
+
+SELECT
+    guests.name,
+    guests.email,
+    checked_out_items.item_id,
+    checked_out_items.due_date
+FROM
+    guests
+LEFT JOIN
+    checked_out_items ON guests.email = checked_out_items.email;