Codeigniter- How to insert different sizes of arrays into database - php

Question

I want to insert data in table 'projects'. I have two arrays with different sizes, they are
$advisor_id = array(
'id' =>1
'id' =>2
'id' =>3
);
$project_id = array(
'pid'=>1
'pid'=>2
'pid'=>3
'pid'=>4
);
My code is:
$advisors = count($this->input->post('advisor_id[]'));
$PM_ids = count($this->input->post('PM_id[]'));
if($advisors > $PM_ids){
$count = $advisors;
}else{
$count = $PM_ids;
}
$data[] = array();
for($i =0; $i<$count ; $i++){
$data = array(
'advisor_id' =>$this->input->post('advisor_id')[$i],
'PM_id' =>$this->input->post('PM_id')[$i],
);
//print_r($data);
$this->db->insert_batch('project_config',$data);
}
My problem is the different sizes of arrays. How can I insert into database.

Answer 1

If you are happy to submit NULL values where missing, array_map() is the best tool for the job.
First a general demonstration of how/where NULL elements are generated when array size mismatches occur...
Code: (Demo)
$advisor_id=['id1'=>1,'id2'=>2,'id3'=>3];
$project_id=['pid1'=>1,'pid2'=>2,'pid3'=>3,'pid4'=>4];
$data=array_map(function($id,$pid){return ['advisor_id'=>$id,'PM_id'=>$pid];},$advisor_id,$project_id);
var_export($data); // see how NULL elements are formed in the output array
Output:
array (
0 =>
array (
'advisor_id' => 1,
'PM_id' => 1,
),
1 =>
array (
'advisor_id' => 2,
'PM_id' => 2,
),
2 =>
array (
'advisor_id' => 3,
'PM_id' => 3,
),
3 =>
array (
'advisor_id' => NULL,
'PM_id' => 4,
),
)
The above multi-dimensional array is now fully prepared for a single insert_batch() call. IMPORTANT CodeIgniter's insert_batch() is specifically designed to INSERT multiple rows of data at once -- to use this call inside of a loop defeats the purpose of making this call.
As for you actual implementation, this should work (I don't code in CodeIgniter):
$data=array_map(function($id,$pid){return ['advisor_id'=>$id,'PM_id'=>$pid];},$this->input->post('advisor_id'),$this->input->post('PM_id'));
$this->db->insert_batch('project_config',$data);
CLEAN & DONE: No for loops, no $i counters, and just one call to the database.