#[cfg(test)]
mod tests {
    use crate::to_sql_string_test;

    // Basic UPDATE with a single column
    to_sql_string_test!(
        test_update_single_column,
        "UPDATE employees SET salary = 55000"
    );

    // UPDATE with multiple columns
    to_sql_string_test!(
        test_update_multiple_columns,
        "UPDATE employees SET salary = 60000, name = 'John Smith'"
    );

    // UPDATE with a WHERE clause
    to_sql_string_test!(
        test_update_with_where,
        "UPDATE employees SET salary = 60000 WHERE id = 1"
    );

    // UPDATE with multiple WHERE conditions
    to_sql_string_test!(
        test_update_with_multi_where,
        "UPDATE employees SET salary = 65000 WHERE department_id = 3 AND salary < 50000"
    );

    // UPDATE with a subquery in SET
    to_sql_string_test!(
        test_update_with_subquery_set,
        "UPDATE employees SET department_id = (SELECT id FROM departments WHERE name = 'Sales') WHERE id = 1"
    );

    // UPDATE with a subquery in WHERE
    to_sql_string_test!(
        test_update_with_subquery_where,
        "UPDATE employees SET salary = 70000 WHERE department_id IN (SELECT id FROM departments WHERE name = 'Marketing')"
    );

    // UPDATE with EXISTS clause
    to_sql_string_test!(
        test_update_with_exists,
        "UPDATE employees SET salary = 75000 WHERE EXISTS (SELECT 1 FROM orders WHERE orders.employee_id = employees.id AND orders.status = 'pending')"
    );

    // UPDATE with FROM clause (join-like behavior)
    to_sql_string_test!(
        test_update_with_from,
        "UPDATE employees SET salary = 80000 FROM departments WHERE employees.department_id = departments.id AND departments.name = 'Engineering'"
    );

    // UPDATE with RETURNING clause
    to_sql_string_test!(
        test_update_with_returning,
        "UPDATE employees SET salary = 60000 WHERE id = 1 RETURNING id, name, salary"
    );

    // UPDATE with expression in SET
    to_sql_string_test!(
        test_update_with_expression,
        "UPDATE employees SET salary = salary * 1.1 WHERE department_id = 2"
    );

    // UPDATE with NULL value
    to_sql_string_test!(
        test_update_with_null,
        "UPDATE employees SET department_id = NULL WHERE id = 1"
    );

    // UPDATE with schema-qualified table
    to_sql_string_test!(
        test_update_schema_qualified,
        "UPDATE main.employees SET salary = 65000 WHERE id = 1"
    );

    // UPDATE with CASE expression
    to_sql_string_test!(
        test_update_with_case,
        "UPDATE employees SET salary = CASE WHEN salary < 50000 THEN 55000 ELSE salary * 1.05 END WHERE department_id = 3"
    );

    // UPDATE with LIKE clause in WHERE
    to_sql_string_test!(
        test_update_with_like,
        "UPDATE employees SET name = 'Updated' WHERE name LIKE 'J%'"
    );

    // UPDATE with ON CONFLICT (upsert-like behavior)
    to_sql_string_test!(
        test_update_with_on_conflict,
        "INSERT INTO employees (id, name, salary) VALUES (1, 'John Doe', 50000) ON CONFLICT (id) DO UPDATE SET name = excluded.name, salary = excluded.salary"
    );
}
