Method begin

packages/core/src/EntityManager.ts:1697–1707

* Starts new transaction bound to this EntityManager. Use `ctx` parameter to provide the parent when nesting transactions.

(options: Omit<TransactionOptions, 'ignoreNestedTransactions'> = {})

   * Starts new transaction bound to this EntityManager. Use `ctx` parameter to provide the parent when nesting transactions.
   */
  async begin(options: Omit<TransactionOptions, 'ignoreNestedTransactions'> = {}): Promise<void> {
    if (this.#disableTransactions) {
      return;
    }

    const em = this.getContext(false);
    em.#transactionContext = await em.getConnection('write').begin({
      ...options,
      eventBroadcaster: new TransactionEventBroadcaster(em, { topLevelTransaction: !options.ctx }),
    });
  }

  /**
   * Commits the transaction bound to this EntityManager. Flushes before doing the actual commit query.