违反完整性约束

Question

我正在尝试使用 drupal-8 将数据插入到 redirect 模块（表：redirect）中的数据库中。

当我第一次插入数据时它工作正常，但是当我再次插入数据时，数据已插入数据库但出现此错误。

function import_redirects($redirects) {
    foreach ($redirects as $from_url => $to_url) {
        Redirect::create([
            'redirect_source' => $from_url,
            'redirect_redirect' => 'internal:/'.$to_url,
            'language' => 'und',
            'status_code' => '301',
            'redirect_redirect__title' => NULL,
        ])->save();
    }
}

错误：

The website encountered an unexpected error. Please try again later.
Drupal\Core\Entity\EntityStorageException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry 'PBx-Sq7RCoQmsJVK-L3pYMpLiKaiyoACLU0atNt6qfE' for key 'hash': INSERT INTO {redirect} (type, uuid, language, hash, uid,` redirect_source__path, redirect_source__query, redirect_redirect__uri, redirect_redirect__title, redirect_redirect__options, status_code, created) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6, :db_insert_placeholder_7, :db_insert_placeholder_8, :db_insert_placeholder_9, :db_insert_placeholder_10, :db_insert_placeholder_11); Array

Answer 1

如果您尝试再次插入相同的条目，它将以相同的散列结束，该散列必须是唯一的。

您应该检查该条目是否已经存在，如果不存在，则插入它，如果存在，则没有理由再次插入它。