CI_DB_query_builder::from PHP Method

    public function from($from)
    {
        foreach ((array) $from as $val) {
            if (strpos($val, ',') !== FALSE) {
                foreach (explode(',', $val) as $v) {
                    $v = trim($v);
                    $this->_track_aliases($v);
                    $this->qb_from[] = $v = $this->protect_identifiers($v, TRUE, NULL, FALSE);
                    if ($this->qb_caching === TRUE) {
                        $this->qb_cache_from[] = $v;
                        $this->qb_cache_exists[] = 'from';
                    }
                }
            } else {
                $val = trim($val);
                // Extract any aliases that might exist. We use this information
                // in the protect_identifiers to know whether to add a table prefix
                $this->_track_aliases($val);
                $this->qb_from[] = $val = $this->protect_identifiers($val, TRUE, NULL, FALSE);
                if ($this->qb_caching === TRUE) {
                    $this->qb_cache_from[] = $val;
                    $this->qb_cache_exists[] = 'from';
                }
            }
        }
        return $this;
    }