如何编写迁移以撤消 Laravel 中的唯一约束？
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How to write a migrate to undo the unique constraint in Laravel?
提问by cyber8200
I would do this to make my email field uniquein the table.
我会这样做以使我的电子邮件字段unique在表格中。
$table->unique('email');
$table->unique('email');
I've tried
我试过了
public function up()
{
Schema::table('contacts', function(Blueprint $table)
{
$table->dropUnique('email');
});
}
Then, when I run php artisan migrate, I got this
然后，当我运行 php artisan migrate 时，我得到了这个
It tell me that it's not there, but I'm 100% sure that it's there.
它告诉我它不在那里，但我 100% 确定它在那里。
How do write a migration to undo that ?
如何编写迁移以撤消该操作？
回答by Ali Gajani
You have to do $table->dropUnique('users_email_unique');
你必须要做 $table->dropUnique('users_email_unique');
To drop an index you must specify the index's name. Laravel assigns a reasonable name to the indexes by default. Simply concatenate the table name, the names of the column in the index, and the index type.
要删除索引，您必须指定索引的名称。默认情况下，Laravel 会为索引分配一个合理的名称。只需连接表名、索引中列的名称和索引类型。
回答by Munna Khan
This the better way to drop unique. You can use the real column name here.
这是放弃唯一性的更好方法。您可以在此处使用真实的列名。
$table->dropUnique(['email']);
