いくつかのコンポーザーのエラーと解決策

composer require sonata-project/doctrine-orm-admin-bundle "2.3.*"

PHP Fatal error:  Allowed memory size of 1610612736 bytes exhausted (tried to allocate 32 bytes)

php -r "echo ini_get('memory_limit').PHP_EOL;"  # 查看memory大小
COMPOSER_MEMORY_LIMIT=-1 composer require sonata-project/doctrine-orm-admin-bundle  # 临时设置memory大小

https://getcomposer.org/doc/articles/troubleshooting.md#memory-limit-errors

but these conflict with your requirements or minimum-stability.

"minimum-stability": "dev",

composer config -g repo.packagist composer https://packagist.phpcomposer.com