sql_to_ER

Convert the following MySQL table-creation SQL into an ER diagram, clearly showing primary keys, foreign keys, and relationships:
CREATE TABLE users (id INT PRIMARY KEY, name VARCHAR(100));
CREATE TABLE orders (id INT PRIMARY KEY, user_id INT, amount DECIMAL(10,2), FOREIGN KEY (user_id) REFERENCES users(id));

An ER diagram showing the users and orders tables with their one-to-many relationship.

Convert this DBML into an ER diagram and optimize the layout for readability:
Table customers {
  id int [pk]
  email varchar
}
Table invoices {
  id int [pk]
  customer_id int [ref: > customers.id]
  total decimal
}

A cleanly laid out ER diagram showing customers, invoices, and their reference relationship.

Generate an ER diagram from the following SQL and help me check for missing foreign keys, redundant fields, or unreasonable relationships.

An ER diagram plus brief review notes on potential schema relationship issues.