php Laravel 5 迁移标识符名称太长
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时间：2020-08-25 21:35:46 来源:igfitidea点击:
Laravel 5 migration identifier name too long
提问by geoffs3310
I am trying to run the following migration:
我正在尝试运行以下迁移：
public function up()
{
Schema::create('lifestyle_questions', function(Blueprint $table)
{
$table->increments('id');
$table->string('question');
$table->timestamps();
});
Schema::create('lifestyle_question_answers', function(Blueprint $table)
{
$table->increments('id');
$table->integer('lifestyle_question_id')->unsigned();
$table->foreign('lifestyle_question_id')->references('id')->on('lifestyle_questions');
$table->string('answer');
$table->timestamps();
});
Schema::create('user_lifestyle_question_answers', function(Blueprint $table)
{
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users');
$table->integer('lifestyle_question_answer_id')->unsigned();
$table->foreign('lifestyle_question_answer_id')->references('id')->on('lifestyle_question_answers');
});
}
But I get the following error:
但我收到以下错误：
[Illuminate\Database\QueryException]
SQLSTATE[42000]: Syntax error or access violation: 1059 Identifier name 'user_lifestyle_question_answers_lifestyle_question_answer_id_foreign' is too long (SQL: alter table `user_lifestyle_question_answers` add constraint user_lifestyle_question_answers_lifestyle_question_answer_id_foreign foreign key (`lifestyle_question_answer_id`) references `lifestyle_question_answers` (`id`))
[PDOException]
SQLSTATE[42000]: Syntax error or access violation: 1059 Identifier name 'user_lifestyle_question_answers_lifestyle_question_answer_id_foreign' is too long
回答by Pawel Bieszczad
You can pass a custom index name as the second parameter into the foreign() method. Or just use shorter table/column names.
您可以将自定义索引名称作为第二个参数传递给 foreign() 方法。或者只是使用较短的表/列名称。
So you want to do something like:
所以你想做这样的事情：
public function up()
{
Schema::create('lifestyle_questions', function(Blueprint $table)
{
$table->increments('id');
$table->string('question');
$table->timestamps();
});
Schema::create('lifestyle_question_answers', function(Blueprint $table)
{
$table->increments('id');
$table->integer('lifestyle_question_id')->unsigned();
$table->foreign('lifestyle_question_id', 'lq_id_foreign')->references('id')->on('lifestyle_questions');
$table->string('answer');
$table->timestamps();
});
Schema::create('user_lifestyle_question_answers', function(Blueprint $table)
{
$table->integer('user_id')->unsigned();
$table->foreign('user_id')->references('id')->on('users');
$table->integer('lifestyle_question_answer_id')->unsigned();
$table->foreign('lifestyle_question_answer_id', 'lqa_id_foreign')->references('id')->on('lifestyle_question_answers');
});
}
