Laravel现有验证

I want to validate the input if the client_id in inserting is existing from the other table

Table where client_id is selected if existing

Schema::create('cluster_members', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('cluster_id')->unsigned()->nullable();
            $table->integer('client_id')->unsigned()->nullable();
            $table->softDeletes();
            $table->timestamps();

});

Table where i will insert the record if passed the validation

Schema::create('loan_applications', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('client_id')->unsigned()->index();
            $table->integer('product_id')->unsigned()->index();


});

So in my Controller

Here is my rule

$rule = ['client_id'=>'required | numeric | exists:clients,id | exists:cluster_members,client_id'];

And this throws me this error

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'id ' in 'where clause'