system/Model.php
public function replace($data = null, bool $returnSQL = false)
	{
		// Validate data before saving.
		if (! empty($data) && $this->skipValidation === false)
		{
			if ($this->validate($data) === false)
			{
				return false;
			}
		}

		return $this->builder()->replace($data, $returnSQL);
	}
public function replace($data = null, bool $returnSQL = false)
	{
		// Validate data before saving.
		if (! empty($data) && $this->skipValidation === false)
		{
			if ($this->validate($data) === false)
			{
				return false;
			}
		}

		return $this->builder()->replace($data, $returnSQL);
	}
Replace

Compiles an replace into string and runs the query

@param null    $data
@param boolean $returnSQL

@return mixed