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

Question

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.

Answer 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