Postgres transaction pattern with pgx: defer rollback, commit explicitly

                  package store

import (
  "context"

  "github.com/jackc/pgx/v5"
)

type Store struct{ db *pgx.Conn }

func (s *Store) CreateOrder(ctx context.Context, userID string, totalCents int64) (string, error) {
  tx, err := s.db.Begin(ctx)
  if err != nil {
    return "", err
  }
  defer func() { _ = tx.Rollback(ctx) }()

  var orderID string
  err = tx.QueryRow(ctx,
    `INSERT INTO orders(user_id, total_cents) VALUES($1, $2) RETURNING id`,
    userID, totalCents,
  ).Scan(&orderID)
  if err != nil {
    return "", err
  }

  _, err = tx.Exec(ctx,
    `INSERT INTO order_audit(order_id, event) VALUES($1, $2)`,
    orderID, "created",
  )
  if err != nil {
    return "", err
  }

  if err := tx.Commit(ctx); err != nil {
    return "", err
  }
  return orderID, nil
}