Here is some content on SQLite data starter packs and links:
CREATE TABLE notes (
id INTEGER PRIMARY KEY AUTOINCREMENT,
title TEXT NOT NULL,
body TEXT,
tags TEXT,
created_at TEXT DEFAULT (datetime('now')),
updated_at TEXT DEFAULT (datetime('now'))
);
SELECT * FROM notes WHERE tags LIKE '%personal%';
I highly recommend bookmarking the SQLite Data Starter Packs repository. Instead of building a backend and an admin panel just to create test data, you can simply run one of these SQL files against your local instance. sqlite data starter packs link
Standardized Schema: Databases like Chinook or Northwind are industry standards, meaning you can find thousands of tutorials online that use these exact tables. Here is some content on SQLite data starter
Census & Education: American Community Survey data and California School SAT Performance/Poverty data . I highly recommend bookmarking the SQLite Data Starter