[李景山php]thinkphp核心源码注释|Sqlite.class.php

<?php// +----------------------------------------------------------------------// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]// +----------------------------------------------------------------------// | Copyright (c) 2006-2014 http://thinkphp.cn All rights reserved.// +----------------------------------------------------------------------// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )// +----------------------------------------------------------------------// | Author: liu21st <[e-mail]>// +----------------------------------------------------------------------namespace Think\Db\Driver;use Think\Db\Driver;/** * Sqlite数据库驱动 */class Sqlite extends Driver {    /**     * 解析pdo连接的dsn信息     * @access public     * @param array $config 连接信息     * @return string     */    protected function parseDsn($config){        $dsn  =   'sqlite:'.$config['database'];        return $dsn;    }    // 这个可以有，这个真心没见过    /**     * 取得数据表的字段信息     * @access public     * @return array     */    public function getFields($tableName) {        list($tableName) = explode(' ', $tableName);        $result =   $this->query('PRAGMA table_info( '.$tableName.' )');        $info   =   array();        if($result){            foreach ($result as $key => $val) {                $info[$val['field']] = array(                    'name'    => $val['field'],                    'type'    => $val['type'],                    'notnull' => (bool) ($val['null'] === ''), // not null is empty, null is yes                    'default' => $val['default'],                    'primary' => (strtolower($val['dey']) == 'pri'),                    'autoinc' => (strtolower($val['extra']) == 'auto_increment'),                );            }        }        return $info;    }    // 这个语句真心简单    /**     * 取得数据库的表信息     * @access public     * @return array     */    public function getTables($dbName='') {        $result =   $this->query("SELECT name FROM sqlite_master WHERE type='table' "             . "UNION ALL SELECT name FROM sqlite_temp_master "             . "WHERE type='table' ORDER BY name");        $info   =   array();        foreach ($result as $key => $val) {            $info[$key] = current($val);        }        return $info;    }    // 评论同上    /**     * SQL指令安全过滤     * @access public     * @param string $str  SQL指令     * @return string     */    public function escapeString($str) {        return str_ireplace("'", "''", $str);    }    // 同上    /**     * limit     * @access public     * @return string     */    public function parseLimit($limit) {        $limitStr    = '';        if(!empty($limit)) {            $limit  =   explode(',',$limit);            if(count($limit)>1) {                $limitStr .= ' LIMIT '.$limit[1].' OFFSET '.$limit[0].' ';            }else{                $limitStr .= ' LIMIT '.$limit[0].' ';            }        }        return $limitStr;    }    // 同上}// 这个很简单，没看懂，默认飘过了............