Laravel 4 Database insert Error - preg_replace(): Parameter mismatch, pattern is a string while replacement is an array

问题

In database seeder, I just want to insert some hard-coded data to the table.

$Pro1_id = DB::table('projects')->select('id')->where('projectName', '=', 'Project A')->get();
    $data1_1 = array(
            'id'                =>      1,
            'projectID'         =>      $Pro1_id,
            'attributeID'       =>      1,
            'levelID'           =>      2,
            'percentage'        =>      20,
            'risk_value'        =>      25186.86311,
            'expectation_value' =>      706455.9401,
        );
    $data1_2 = array(
            'projectID'         =>      $Pro1_id,
            'attributeID'       =>      2,
            'levelID'           =>      1,
            'percentage'        =>      60,
            'risk_value'        =>      530351.3397,
            'expectation_value' =>      392207.1248,
        );
    $data1 = [$data1_1, $data1_2];
    DB::table('Mapping')->insert($data1);

However, I got the error:

[ErrorException] preg_replace(): Parameter mismatch, pattern is a string while replacement is an array

It is so weird, because I did the same to another table, it worked.

DB::table('projects')->insert(array(
                array(
                    'id'            =>  Webpatser\Uuid\Uuid::generate(),
                    'projectName'   =>  'Project A',
                    'creator_id'    =>  $pro1_creatorID,
                    'create_at'     =>  \Carbon\Carbon::now()->toDateString(),
                    'lastEditor_id' =>  $pro1_creatorID,
                    'edit_at'       =>  \Carbon\Carbon::now()->toDateString(),
                    'utility'       =>  1.597119661,
                    'exponential'   =>  4.94,
                    'projectValue'  =>  1225090.39
                ),
                array(
                    'id'              =>  Webpatser\Uuid\Uuid::generate(),
                    'projectName'   =>  'Project B',
                    'creator_id'    =>  $pro2_creatorID,
                    'create_at'     =>  \Carbon\Carbon::create(2014, 12, 12)->toDateString(),
                    'lastEditor_id' =>  $pro2_creatorID,
                    'edit_at'       =>  \Carbon\Carbon::create(2014, 12, 12)->toDateString(),
                    'utility'       =>  1.754989409,
                    'exponential'   =>  5.78,
                    'projectValue'  =>  293760.36
                ),
                array(
                    'id'              =>  Webpatser\Uuid\Uuid::generate(),
                    'projectName'   =>  'Project C',
                    'creator_id'    =>  $pro3_creatorID,
                    'create_at'     =>  \Carbon\Carbon::create(2013, 10, 21)->toDateString(),
                    'lastEditor_id' =>  $pro3_creatorID,
                    'edit_at'       =>  \Carbon\Carbon::create(2013, 10, 21)->toDateString(),
                    'utility'       =>  1.423114267,
                    'exponential'   =>  4.15,
                    'projectValue'  =>  1461924.67

                )
            )
        );

I really don't understand why inserting into projects table works, but the one of the mapping table does NOT work. They are exactly the same method.

回答1:

I think your code is correct but when you insert the id in array, you are doing the wrong way.

$Pro1_id = DB::table('projects')->select('id')->where('projectName', '=', 'Project A')->get();

Here, $Pro1_id is Collection that contain value return from your query. Sometimes it might be one, but sometimes it might be 2 or 3.... So , your are doing the wrong way when you are inserting the id in the array. So , use foreach loop like this :

foreach($Pro1_id as $pro){
    DB::table('Mapping')->insert(array(
            'id'                =>      1,
            'projectID'         =>      $pro->id,
            'attributeID'       =>      1,
            'levelID'           =>      2,
            'percentage'        =>      20,
            'risk_value'        =>      25186.86311,
            'expectation_value' =>      706455.9401,
        ));
}

For simple , get returns Collection and is rather supposed to fetch multiple rows.

For more info . Check this

来源：https://stackoverflow.com/questions/33339520/laravel-4-database-insert-error-preg-replace-parameter-mismatch-pattern-is