Php Laravel 5迁移标识符名称太长
我正在尝试运行以下迁移:Php Laravel 5迁移标识符名称太长,php,laravel,eloquent,laravel-5,Php,Laravel,Eloquent,Laravel 5,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('l
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');
});
}
但我得到了以下错误:
[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
可以将自定义索引名作为第二个参数传递给foreign()方法。或者只使用较短的表/列名 所以你想做一些类似的事情:
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();
$table->foreign('lifestyle_question_answer_id', 'lqa_id_foreign')->references('id')->on('lifestyle_question_answers');
});
}
仅供参考:MySQL标识符应始终少于64个字符。不幸的是,此解决方案在生成复合键时不适用于
primary()
method:$table->primary(['id1','id'],'custom_index')
如何解决这个问题?对于那些在生成@Dong3000这样的复合键时遇到这个问题的人,请参见:对于使用foreignd
的人,您可以这样使用它:$table->foreignd('really_long\u foreign\u key\id')->constrated()->index('short\id\u foreign')代码>