CodeIgniter work with db

Select single value from db

public function selectSingleValue($row,$sql,$params=null){
         $data = $this->db->query($sql,$params)
                          ->row($row);
         return $data;
 }

//Usage example

$value = selectSingleValue('value', 'Select value from table where id=?', array($id));

Select single row from db

public function selectSingleRow($sql,$params=null){
         $data = $this->db->query($sql, $params)
                          ->row_array();
         return $data;
 
  }

//Usage example

$data = selectSingleRow('Select * from table where id=?', array($id));

Select multiple rows from db

public function selectMultyRow($sql,$params=null){
         $data = $this->db->query($sql, $params)
                          ->result_array();
         return $data;
 
  } 

//Usage example

$data = selectMultyRow('Select * from table where id=?', array($id));

Insert data and get last inserted id

 public function insertData ($table, $data){           
         $this->db->insert($table,$data );       
         return $this->db->insert_id();

//Usage example
$data=array(
       'name'=>'Demax',
       'gender'=>'male',
       'type'=>'user'
);


$id = insertData('table', $data);

Update data

//Usage example


$data=array(
       'name'=>'Demax',
       'gender'=>'male',
       'type'=>'admin'
);

$this->db->update('mytable', $data, array('id' => $id));

Delete data

//Usage example

$this->db->delete('mytable', array('id' => $id));

//Performs "Delete from mytable where id=$id"