【CodeIgniter3】クエリビルダーにINSERT ON DUPLICATE KEY UPDATE構文によるバッチ処理を追加する方法

MY_DB_query_builder.php

<?php

defined('BASEPATH') OR exit('No direct script access allowed');

class CI_DB extends MY_DB_query_builder
{
	
}

class MY_DB_query_builder extends CI_DB_query_builder
{

	/**
	 * Insert_On_Duplicate_Key_Update_Batch
	 *
	 * Compiles batch insert strings and runs the queries
	 *
	 * @param	string	$table	Table to insert into
	 * @param	array	$set 	An associative array of insert values
	 * @param	bool	$escape	Whether to escape values and identifiers
	 * @return	int	Number of rows inserted or FALSE on failure
	 */
	public function insert_on_duplicate_update_batch($table = '', $set = NULL, $escape = NULL)
	{
		if ($set !== NULL)
		{
			$this->set_insert_batch($set, '', $escape);
		}
		
		if (count($this->qb_set) === 0)
		{
			// No valid data array. Folds in cases where keys and values did not match up
			return ($this->db_debug) ? $this->display_error('db_must_use_set') : FALSE;
		}
		
		if ($table === '')
		{
			if (!isset($this->qb_from[0]))
			{
				return ($this->db_debug) ? $this->display_error('db_must_set_table') : FALSE;
			}
			$table = $this->qb_from[0];
		}
		
		// Batch this baby
		$affected_rows = 0;
		for ($i = 0, $total = count($this->qb_set); $i < $total; $i += 100)
		{
			$this->query($this->_insert_on_duplicate_key_update_batch($this->protect_identifiers($table, TRUE, $escape, FALSE), $this->qb_keys, array_slice($this->qb_set, $i, 100)));
			$affected_rows += $this->affected_rows();
		}
		$this->_reset_write();
		return $affected_rows;
	}

	/**
	 * Insert on duplicate key update batch statement
	 *
	 * Generates a platform-specific insert string from the supplied data
	 *
	 * @param	string	$table	Table name
	 * @param	array	$keys	INSERT keys
	 * @param	array	$values	INSERT values
	 * @return	string
	 */
	private function _insert_on_duplicate_key_update_batch($table, $keys, $values)
	{
		foreach ($keys as $num => $key)
		{
			$update_fields[] = $key . '= VALUES(' . $key . ')';
		}
		
		return "INSERT INTO " . $table . " (" . implode(', ', $keys) . ") VALUES " . implode(', ', $values) . " ON DUPLICATE KEY UPDATE " . implode(', ', $update_fields);
	}

}