system/classes/Database.php
protected function storeValue($type, $data, $delim = false)
     {
         $dataMember = &$this->$type;
         // If array or object full of data was passed in, add all data
         // to appropriate data member.
         if (is_array($data) || is_object($data)) {
             foreach ($data as $value) {
                 if ($value !== false) {
                     if ($delim) {
                         $value = $delim.$value.$delim;
                     }
                 }
                 else {
                     $value = 'NULL';
                 }
                 array_push($dataMember, $value);
             }
         }

         // Add singular data item to data member.
         else {
             if ($data !== false) {
                 if ($delim) {
                     $data = $delim.$data.$delim;
                 }
             }
             else {
                 $data = 'NULL';
             }
             array_push($dataMember, $data);
         }
     }
protected function storeValue($type, $data, $delim = false)
     {
         $dataMember = &$this->$type;
         // If array or object full of data was passed in, add all data
         // to appropriate data member.
         if (is_array($data) || is_object($data)) {
             foreach ($data as $value) {
                 if ($value !== false) {
                     if ($delim) {
                         $value = $delim.$value.$delim;
                     }
                 }
                 else {
                     $value = 'NULL';
                 }
                 array_push($dataMember, $value);
             }
         }

         // Add singular data item to data member.
         else {
             if ($data !== false) {
                 if ($delim) {
                     $data = $delim.$data.$delim;
                 }
             }
             else {
                 $data = 'NULL';
             }
             array_push($dataMember, $data);
         }
     }
For storing a single value or flat list of values.
STORAGE FORMAT:
[item1, item2, item3]