Insert data from array_push to database in codeigniter - php

Question

Hi i hava data in array like this :
$data = Array
(
[0] => Array
(
[kode_pbt] => PBT3-2012-10-19
[kodebr] => 8992802618731
[harga] => 25905.00
[jml] => 1
[subtotal_harga] => 25905
)
[1] => Array
(
[kode_pbt] => PBT3-2012-10-19
[kodebr] => 8992388112401
[harga] => 1340.00
[jml] => 1
[subtotal_harga] => 1340
)
)
my problem is when i want to insert to database
white this code : $this->db->insert($table, $data)
i got an error:
Message: Array to string conversion
I have changed to $this->db->insert_batch($table, $data), but i got error '500 internal server error'.
Thank for your assist.
This is my full function code in controller :
function save_pbt($kode = -1) {
$pbt_detail = array();
$pbt_data = array(
'kode_pbt' => trim($this->input->post('kode_pbt')),
'unit_pemakai' => trim($this->input->post('unit_pemakai')),
'jml_item' => trim($this->input->post('jml_item')),
'total_harga' => trim($this->input->post('total_harga')),
'tgl_pbt' => date('Y-m-d'),
'status' => 0
);
for ($i = 0; $i <= $this->input->post('max_i'); $i++) {
if ($this->input->post('kodebr' . $i)) {
$detail_pbt = array(
'kode_pbt' => $this->input->post('kode_pbt'),
'kodebr' => $this->input->post('kodebr' . $i),
'harga' => $this->input->post('beli' . $i),
'jml' => $this->input->post('jml' . $i),
'subtotal_harga' => $this->input->post('subtotal' . $i)
);
array_push($pbt_detail, $detail_pbt);
}
}
$this->db->trans_begin();
$this->Pbt_model->insert_pbt($pbt_data);
$this->Pbt_model->insert_detail_pbt($pbt_detail);
if ($this->db->trans_status() == FALSE) {
$this->db->trans_rollback();
echo "TRANSACTION ROLLBACK";
} else {
$pbt_data['detail'] = $pbt_detail;
$url = SERVER_SIKOPIT . 'service/service?process=pbt&api_key=' . API_KEY;
$response = json_encode($this->rest_helper($url, $pbt_data, "POST"));
echo $response;
$response = json_decode($response);
if ($response->status == true) {
$this->db->trans_commit();
echo "TRANSACTION SUCCESS";
redirect(site_url('receivings'));
} else {
$this->db->trans_rollback();
echo "INSERT PBT BARU GAGAL !!";
echo "TRANSACTION ROLLBACK";
}
}
}