<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
/**
* ThinkPHP 数据库中间层实现类
* @category Think
* @package Think
* @subpackage Core
* @author liu21st <liu21st@gmail.com>
*/
class Db {
// 数据库类型
protected $dbType = null;
// 是否自动释放查询结果
protected $autoFree = false;
// 当前操作所属的模型名
protected $model = '_think_';
// 是否使用永久连接
protected $pconnect = false;
// 当前SQL指令
protected $queryStr = '';
protected $modelSql = array();
// 最后插入ID
protected $lastInsID = null;
// 返回或者影响记录数
protected $numRows = 0;
// 返回字段数
protected $numCols = 0;
// 事务指令数
protected $transTimes = 0;
// 错误信息
protected $error = '';
// 数据库连接ID 支持多个连接
protected $linkID = array();
// 当前连接ID
protected $_linkID = null;
// 当前查询ID
protected $queryID = null;
// 是否已经连接数据库
protected $connected = false;
// 数据库连接参数配置
protected $config = '';
// 数据库表达式
protected $comparison = array('eq'=>'=','neq'=>'<>','gt'=>'>','egt'=>'>=','lt'=>'<','elt'=>'<=','notlike'=>'NOT LIKE','like'=>'LIKE','in'=>'IN','notin'=>'NOT IN');
// 查询表达式
protected $selectSql = 'SELECT%DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%%ORDER%%LIMIT% %UNION%%COMMENT%';
/**
* 取得数据库类实例
* @static
* @access public
* @return mixed 返回数据库驱动类
*/
public static function getInstance() {
$args = func_get_args();
return get_instance_of(__CLASS__,'factory',$args);
}
/**
* 加载数据库 支持配置文件或者 DSN
* @access public
* @param mixed $db_config 数据库配置信息
* @return string
*/
public function factory($db_config='') {
// 读取数据库配置
$db_config = $this->parseConfig($db_config);
if(empty($db_config['dbms']))
throw_exception(L('_NO_DB_CONFIG_'));
// 数据库类型
$this->dbType = ucwords(strtolower($db_config['dbms']));
$class = 'Db'. $this->dbType;
// 检查驱动类
if(class_exists($class)) {
$db = new $class($db_config);
// 获取当前的数据库类型
if( 'pdo' != strtolower($db_config['dbms']) )
$db->dbType = strtoupper($this->dbType);
else
$db->dbType = $this->_getDsnType($db_config['dsn']);
}else {
// 类没有定义
throw_exception(L('_NO_DB_DRIVER_').': ' . $class);
}
return $db;
}
/**
* 根据DSN获取数据库类型 返回大写
* @access protected
* @param string $dsn dsn字符串
* @return string
*/
protected function _getDsnType($dsn) {
$match = explode(':',$dsn);
$dbType = strtoupper(trim($match[0]));
return $dbType;
}
/**
* 分析数据库配置信息，支持数组和DSN
* @access private
* @param mixed $db_config 数据库配置信息
* @return string
*/
private function parseConfig($db_config='') {
if ( !empty($db_config) && is_string($db_config)) {
// 如果DSN字符串则进行解析
$db_config = $this->parseDSN($db_config);
}elseif(is_array($db_config)) { // 数组配置
$db_config = array_change_key_case($db_config);
$db_config = array(
'dbms' => $db_config['db_type'],
'username' => $db_config['db_user'],
'password' => $db_config['db_pwd'],
'hostname' => $db_config['db_host'],
'hostport' => $db_config['db_port'],
'database' => $db_config['db_name'],
'dsn' => $db_config['db_dsn'],
'params' => $db_config['db_params'],
);
}elseif(empty($db_config)) {
// 如果配置为空，读取配置文件设置
if( C('DB_DSN') && 'pdo' != strtolower(C('DB_TYPE')) ) { // 如果设置了DB_DSN 则优先
$db_config = $this->parseDSN(C('DB_DSN'));
}else{
$db_config = array (
'dbms' => C('DB_TYPE'),
'username' => C('DB_USER'),
'password' => C('DB_PWD'),
'hostname' => C('DB_HOST'),
'hostport' => C('DB_PORT'),
'database' => C('DB_NAME'),
'dsn' => C('DB_DSN'),
'params' => C('DB_PARAMS'),
);
}
}
return $db_config;
}
/**
* 初始化数据库连接
* @access protected
* @param boolean $master 主服务器
* @return void
*/
protected function initConnect($master=true) {
if(1 == C('DB_DEPLOY_TYPE'))
// 采用分布式数据库
$this->_linkID = $this->multiConnect($master);
else
// 默认单数据库
if ( !$this->connected ) $this->_linkID = $this->connect();
}
/**
* 连接分布式服务器
* @access protected
* @param boolean $master 主服务器
* @return void
*/
protected function multiConnect($master=false) {
static $_config = array();
if(empty($_config)) {
// 缓存分布式数据库配置解析
foreach ($this->config as $key=>$val){
$_config[$key] = explode(',',$val);
}
}
// 数据库读写是否分离
if(C('DB_RW_SEPARATE')){
// 主从式采用读写分离
if($master)
// 主服务器写入
$r = floor(mt_rand(0,C('DB_MASTER_NUM')-1));
else{
if(is_numeric(C('DB_SLAVE_NO'))) {// 指定服务器读
$r = C('DB_SLAVE_NO');
}else{
// 读操作连接从服务器
$r = floor(mt_rand(C('DB_MASTER_NUM'),count($_config['hostname'])-1)); // 每次随机连接的数据库
}
}
}else{
// 读写操作不区分服务器
$r = floor(mt_rand(0,count($_config['hostname'])-1)); // 每次随机连接的数据库
}
$db_config = array(
'username' => isset($_config['username'][$r])?$_config['username'][$r]:$_config['username'][0],
'password' => isset($_config['password'][$r])?$_config['password'][$r]:$_config['password'][0],
'hostname' => isset($_config['hostname'][$r])?$_config['hostname'][$r]:$_config['hostname'][0],
'hostport' => isset($_config['hostport'][$r])?$_config['hostport'][$r]:$_config['hostport'][0],
'database' => isset($_config['database'][$r])?$_config['database'][$r]:$_config['database'][0],
'dsn' => isset($_config['dsn'][$r])?$_config['dsn'][$r]:$_config['dsn'][0],
'params' => isset($_config['params'][$r])?$_config['params'][$r]:$_config['params'][0],
);
return $this->connect($db_config,$r);
}
/**
* DSN解析
* 格式： mysql://username:passwd@localhost:3306/DbName
* @static
* @access public
* @param string $dsnStr
* @return array
*/
public function parseDSN($dsnStr) {
if( empty($dsnStr) ){return false;}
$info = parse_url($dsnStr);
if($info['scheme']){
$dsn = array(
'dbms' => $info['scheme'],
'username' => isset($info['user']) ? $info['user'] : '',
'password' => isset($info['pass']) ? $info['pass'] : '',
'hostname' => isset($info['host']) ? $info['host'] : '',
'hostport' => isset($info['port']) ? $info['port'] : '',
'database' => isset($info['path']) ? substr($info['path'],1) : ''
);
}else {
preg_match('/^(.*?)\:\/\/(.*?)\:(.*?)\@(.*?)\:([0-9]{1, 6})\/(.*?)$/',trim($dsnStr),$matches);
$dsn = array (
'dbms' => $matches[1],
'username' => $matches[2],
'password' => $matches[3],
'hostname' => $matches[4],
'hostport' => $matches[5],
'database' => $matches[6]
);
}
$dsn['dsn'] = ''; // 兼容配置信息数组
return $dsn;
}
/**
* 数据库调试 记录当前SQL
* @access protected
*/
protected function debug() {
$this->modelSql[$this->model] = $this->queryStr;
$this->model = '_think_';
// 记录操作结束时间
if (C('DB_SQL_LOG')) {
G('queryEndTime');
trace($this->queryStr.' [ RunTime:'.G('queryStartTime','queryEndTime',6).'s ]','','SQL');
}
}
/**
* 设置锁机制
* @access protected
* @return string
*/
protected function parseLock($lock=false) {
if(!$lock) return '';
if('ORACLE' == $this->dbType) {
return ' FOR UPDATE NOWAIT ';
}
return ' FOR UPDATE ';
}
/**
* set分析
* @access protected
* @param array $data
* @return string
*/
protected function parseSet($data) {
foreach ($data as $key=>$val){
$value = $this->parseValue($val);
if(is_scalar($value)) // 过滤非标量数据
$set[] = $this->parseKey($key).'='.$value;
}
return ' SET '.implode(',',$set);
}
/**
* 字段名分析
* @access protected
* @param string $key
* @return string
*/
protected function parseKey(&$key) {
return $key;
}
/**
* value分析
* @access protected
* @param mixed $value
* @return string
*/
protected function parseValue($value) {
if(is_string($value)) {
$value = '\''.$this->escapeString($value).'\'';
}elseif(isset($value[0]) && is_string($value[0]) && strtolower($value[0]) == 'exp'){
$value = $this->escapeString($value[1]);
}elseif(is_array($value)) {
$value = array_map(array($this, 'parseValue'),$value);
}elseif(is_bool($value)){
$value = $value ? '1' : '0';
}elseif(is_null($value)){
$value = 'null';
}
return $value;
}
/**
* field分析
* @access protected
* @param mixed $fields
* @return string
*/
protected function parseField($fields) {
if(is_string($fields) && strpos($fields,',')) {
$fields = explode(',',$fields);
}
if(is_array($fields)) {
// 完善数组方式传字段名的支持
// 支持 'field1'=>'field2' 这样的字段别名定义
$array = array();
foreach ($fields as $key=>$field){
if(!is_numeric($key))
$array[] = $this->parseKey($key).' AS '.$this->parseKey($field);
else
$array[] = $this->parseKey($field);
}
$fieldsStr = implode(',', $array);
}elseif(is_string($fields) && !empty($fields)) {
$fieldsStr = $this->parseKey($fields);
}else{
$fieldsStr = '*';
}
//TODO 如果是查询全部字段，并且是join的方式，那么就把要查的表加个别名，以免字段被覆盖
return $fieldsStr;
}
/**
* table分析
* @access protected
* @param mixed $table
* @return string
*/
protected function parseTable($tables) {
if(is_array($tables)) {// 支持别名定义
$array = array();
foreach ($tables as $table=>$alias){
if(!is_numeric($table))
$array[] = $this->parseKey($table).' '.$this->parseKey($alias);
else
$array[] = $this->parseKey($table);
}
$tables = $array;
}elseif(is_string($tables)){
$tables = explode(',',$tables);
array_walk($tables, array(&$this, 'parseKey'));
}
return implode(',',$tables);
}
/**
* where分析
* @access protected
* @param mixed $where
* @return string
*/
protected function parseWhere($where) {
$whereStr = '';
if(is_string($where)) {
// 直接使用字符串条件
$whereStr = $where;
}else{ // 使用数组表达式
$operate = isset($where['_logic'])?strtoupper($where['_logic']):'';
if(in_array($operate,array('AND','OR','XOR'))){
// 定义逻辑运算规则 例如 OR XOR AND NOT
$operate = ' '.$operate.' ';
unset($where['_logic']);
}else{
// 默认进行 AND 运算
$operate = ' AND ';
}
foreach ($where as $key=>$val){
$whereStr .= '( ';
if(0===strpos($key,'_')) {
// 解析特殊条件表达式
$whereStr .= $this->parseThinkWhere($key,$val);
}else{
// 查询字段的安全过滤
if(!preg_match('/^[A-Z_\|\&\-.a-z0-9\(\)\,]+$/',trim($key))){
throw_exception(L('_EXPRESS_ERROR_').':'.$key);
}
// 多条件支持
$multi = is_array($val) && isset($val['_multi']);
$key = trim($key);
if(strpos($key,'|')) { // 支持 name|title|nickname 方式定义查询字段
$array = explode('|',$key);
$str = array();
foreach ($array as $m=>$k){
$v = $multi?$val[$m]:$val;
$str[] = '('.$this->parseWhereItem($this->parseKey($k),$v).')';
}
$whereStr .= implode(' OR ',$str);
}elseif(strpos($key,'&')){
$array = explode('&',$key);
$str = array();
foreach ($array as $m=>$k){
$v = $multi?$val[$m]:$val;
$str[] = '('.$this->parseWhereItem($this->parseKey($k),$v).')';
}
$whereStr .= implode(' AND ',$str);
}else{
$whereStr .= $this->parseWhereItem($this->parseKey($key),$val);
}
}
$whereStr .= ' )'.$operate;
}
$whereStr = substr($whereStr,0,-strlen($operate));
}
return empty($whereStr)?'':' WHERE '.$whereStr;
}
// where子单元分析
protected function parseWhereItem($key,$val) {
$whereStr = '';
if(is_array($val)) {
if(is_string($val[0])) {
if(preg_match('/^(EQ|NEQ|GT|EGT|LT|ELT)$/i',$val[0])) { // 比较运算
$whereStr .= $key.' '.$this->comparison[strtolower($val[0])].' '.$this->parseValue($val[1]);
}elseif(preg_match('/^(NOTLIKE|LIKE)$/i',$val[0])){// 模糊查找
if(is_array($val[1])) {
$likeLogic = isset($val[2])?strtoupper($val[2]):'OR';
if(in_array($likeLogic,array('AND','OR','XOR'))){
$likeStr = $this->comparison[strtolower($val[0])];
$like = array();
foreach ($val[1] as $item){
$like[] = $key.' '.$likeStr.' '.$this->parseValue($item);
}
$whereStr .= '('.implode(' '.$likeLogic.' ',$like).')';
}
}else{
$whereStr .= $key.' '.$this->comparison[strtolower($val[0])].' '.$this->parseValue($val[1]);
}
}elseif('exp'==strtolower($val[0])){ // 使用表达式
$whereStr .= ' ('.$key.' '.$val[1].') ';
}elseif(preg_match('/IN/i',$val[0])){ // IN 运算
if(isset($val[2]) && 'exp'==$val[2]) {
$whereStr .= $key.' '.strtoupper($val[0]).' '.$val[1];
}else{
if(is_string($val[1])) {
$val[1] = explode(',',$val[1]);
}
$zone = implode(',',$this->parseValue($val[1]));
$whereStr .= $key.' '.strtoupper($val[0]).' ('.$zone.')';
}
}elseif(preg_match('/BETWEEN/i',$val[0])){ // BETWEEN运算
$data = is_string($val[1])? explode(',',$val[1]):$val[1];
$whereStr .= ' ('.$key.' '.strtoupper($val[0]).' '.$this->parseValue($data[0]).' AND '.$this->parseValue($data[1]).' )';
}else{
throw_exception(L('_EXPRESS_ERROR_').':'.$val[0]);
}
}else {
$count = count($val);
$rule = isset($val[$count-1])?strtoupper($val[$count-1]):'';
if(in_array($rule,array('AND','OR','XOR'))) {
$count = $count -1;
}else{
$rule = 'AND';
}
for($i=0;$i<$count;$i++) {
$data = is_array($val[$i])?$val[$i][1]:$val[$i];
if('exp'==strtolower($val[$i][0])) {
$whereStr .= '('.$key.' '.$data.') '.$rule.' ';
}else{
$op = is_array($val[$i])?$this->comparison[strtolower($val[$i][0])]:'=';
$whereStr .= '('.$key.' '.$op.' '.$this->parseValue($data).') '.$rule.' ';
}
}
$whereStr = substr($whereStr,0,-4);
}
}else {
//对字符串类型字段采用模糊匹配
if(C('DB_LIKE_FIELDS') && preg_match('/('.C('DB_LIKE_FIELDS').')/i',$key)) {
$val = '%'.$val.'%';
$whereStr .= $key.' LIKE '.$this->parseValue($val);
}else {
$whereStr .= $key.' = '.$this->parseValue($val);
}
}
return $whereStr;
}
/**
* 特殊条件分析
* @access protected
* @param string $key
* @param mixed $val
* @return string
*/
protected function parseThinkWhere($key,$val) {
$whereStr = '';
switch($key) {
case '_string':
// 字符串模式查询条件
$whereStr = $val;
break;
case '_complex':
// 复合查询条件
$whereStr = substr($this->parseWhere($val),6);
break;
case '_query':
// 字符串模式查询条件
parse_str($val,$where);
if(isset($where['_logic'])) {
$op = ' '.strtoupper($where['_logic']).' ';
unset($where['_logic']);
}else{
$op = ' AND ';
}
$array = array();
foreach ($where as $field=>$data)
$array[] = $this->parseKey($field).' = '.$this->parseValue($data);
$whereStr = implode($op,$array);
break;
}
return $whereStr;
}
/**
* limit分析
* @access protected
* @param mixed $lmit
* @return string
*/
protected function parseLimit($limit) {
return !empty($limit)? ' LIMIT '.$limit.' ':'';
}
/**
* join分析
* @access protected
* @param mixed $join
* @return string
*/
protected function parseJoin($join) {
$joinStr = '';
if(!empty($join)) {
if(is_array($join)) {
foreach ($join as $key=>$_join){
if(false !== stripos($_join,'JOIN'))
$joinStr .= ' '.$_join;
else
$joinStr .= ' LEFT JOIN ' .$_join;
}
}else{
$joinStr .= ' LEFT JOIN ' .$join;
}
}
//将__TABLE_NAME__这样的字符串替换成正规的表名,并且带上前缀和后缀
$joinStr = preg_replace("/__([A-Z_-]+)__/esU",C("DB_PREFIX").".strtolower('$1')",$joinStr);
return $joinStr;
}
/**
* order分析
* @access protected
* @param mixed $order
* @return string
*/
protected function parseOrder($order) {
if(is_array($order)) {
$array = array();
foreach ($order as $key=>$val){
if(is_numeric($key)) {
$array[] = $this->parseKey($val);
}else{
$array[] = $this->parseKey($key).' '.$val;
}
}
$order = implode(',',$array);
}
return !empty($order)? ' ORDER BY '.$order:'';
}
/**
* group分析
* @access protected
* @param mixed $group
* @return string
*/
protected function parseGroup($group) {
return !empty($group)? ' GROUP BY '.$group:'';
}
/**
* having分析
* @access protected
* @param string $having
* @return string
*/
protected function parseHaving($having) {
return !empty($having)? ' HAVING '.$having:'';
}
/**
* comment分析
* @access protected
* @param string $comment
* @return string
*/
protected function parseComment($comment) {
return !empty($comment)? ' /* '.$comment.' */':'';
}
/**
* distinct分析
* @access protected
* @param mixed $distinct
* @return string
*/
protected function parseDistinct($distinct) {
return !empty($distinct)? ' DISTINCT ' :'';
}
/**
* union分析
* @access protected
* @param mixed $union
* @return string
*/
protected function parseUnion($union) {
if(empty($union)) return '';
if(isset($union['_all'])) {
$str = 'UNION ALL ';
unset($union['_all']);
}else{
$str = 'UNION ';
}
foreach ($union as $u){
$sql[] = $str.(is_array($u)?$this->buildSelectSql($u):$u);
}
return implode(' ',$sql);
}
/**
* 插入记录
* @access public
* @param mixed $data 数据
* @param array $options 参数表达式
* @param boolean $replace 是否replace
* @return false | integer
*/
public function insert($data,$options=array(),$replace=false) {
$values = $fields = array();
$this->model = $options['model'];
foreach ($data as $key=>$val){
$value = $this->parseValue($val);
if(is_scalar($value)) { // 过滤非标量数据
$values[] = $value;
$fields[] = $this->parseKey($key);
}
}
$sql = ($replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES ('.implode(',', $values).')';
$sql .= $this->parseLock(isset($options['lock'])?$options['lock']:false);
$sql .= $this->parseComment(!empty($options['comment'])?$options['comment']:'');
return $this->execute($sql);
}
/**
* 通过Select方式插入记录
* @access public
* @param string $fields 要插入的数据表字段名
* @param string $table 要插入的数据表名
* @param array $option 查询数据参数
* @return false | integer
*/
public function selectInsert($fields,$table,$options=array()) {
$this->model = $options['model'];
if(is_string($fields)) $fields = explode(',',$fields);
array_walk($fields, array($this, 'parseKey'));
$sql = 'INSERT INTO '.$this->parseTable($table).' ('.implode(',', $fields).') ';
$sql .= $this->buildSelectSql($options);
return $this->execute($sql);
}
/**
* 更新记录
* @access public
* @param mixed $data 数据
* @param array $options 表达式
* @return false | integer
*/
public function update($data,$options) {
$this->model = $options['model'];
$sql = 'UPDATE '
.$this->parseTable($options['table'])
.$this->parseSet($data)
.$this->parseWhere(!empty($options['where'])?$options['where']:'')
.$this->parseOrder(!empty($options['order'])?$options['order']:'')
.$this->parseLimit(!empty($options['limit'])?$options['limit']:'')
.$this->parseLock(isset($options['lock'])?$options['lock']:false)
.$this->parseComment(!empty($options['comment'])?$options['comment']:'');
return $this->execute($sql);
}
/**
* 删除记录
* @access public
* @param array $options 表达式
* @return false | integer
*/
public function delete($options=array()) {
$this->model = $options['model'];
$sql = 'DELETE FROM '
.$this->parseTable($options['table'])
.$this->parseWhere(!empty($options['where'])?$options['where']:'')
.$this->parseOrder(!empty($options['order'])?$options['order']:'')
.$this->parseLimit(!empty($options['limit'])?$options['limit']:'')
.$this->parseLock(isset($options['lock'])?$options['lock']:false)
.$this->parseComment(!empty($options['comment'])?$options['comment']:'');
return $this->execute($sql);
}
/**
* 查找记录
* @access public
* @param array $options 表达式
* @return mixed
*/
public function select($options=array()) {
$this->model = $options['model'];
$sql = $this->buildSelectSql($options);
$cache = isset($options['cache'])?$options['cache']:false;
if($cache) { // 查询缓存检测
$key = is_string($cache['key'])?$cache['key']:md5($sql);
$value = S($key,'',$cache);
if(false !== $value) {
return $value;
}
}
$result = $this->query($sql);
if($cache && false !== $result ) { // 查询缓存写入
S($key,$result,$cache);
}
return $result;
}
/**
* 生成查询SQL
* @access public
* @param array $options 表达式
* @return string
*/
public function buildSelectSql($options=array()) {
if(isset($options['page'])) {
// 根据页数计算limit
if(strpos($options['page'],',')) {
list($page,$listRows) = explode(',',$options['page']);
}else{
$page = $options['page'];
}
$page = $page?$page:1;
$listRows= isset($listRows)?$listRows:(is_numeric($options['limit'])?$options['limit']:20);
$offset = $listRows*((int)$page-1);
$options['limit'] = $offset.','.$listRows;
}
if(C('DB_SQL_BUILD_CACHE')) { // SQL创建缓存
$key = md5(serialize($options));
$value = S($key);
if(false !== $value) {
return $value;
}
}
$sql = $this->parseSql($this->selectSql,$options);
$sql .= $this->parseLock(isset($options['lock'])?$options['lock']:false);
if(isset($key)) { // 写入SQL创建缓存
S($key,$sql,array('expire'=>0,'length'=>C('DB_SQL_BUILD_LENGTH'),'queue'=>C('DB_SQL_BUILD_QUEUE')));
}
return $sql;
}
/**
* 替换SQL语句中表达式
* @access public
* @param array $options 表达式
* @return string
*/
public function parseSql($sql,$options=array()){
$sql = str_replace(
array('%TABLE%','%DISTINCT%','%FIELD%','%JOIN%','%WHERE%','%GROUP%','%HAVING%','%ORDER%','%LIMIT%','%UNION%','%COMMENT%'),
array(
$this->parseTable($options['table']),
$this->parseDistinct(isset($options['distinct'])?$options['distinct']:false),
$this->parseField(!empty($options['field'])?$options['field']:'*'),
$this->parseJoin(!empty($options['join'])?$options['join']:''),
$this->parseWhere(!empty($options['where'])?$options['where']:''),
$this->parseGroup(!empty($options['group'])?$options['group']:''),
$this->parseHaving(!empty($options['having'])?$options['having']:''),
$this->parseOrder(!empty($options['order'])?$options['order']:''),
$this->parseLimit(!empty($options['limit'])?$options['limit']:''),
$this->parseUnion(!empty($options['union'])?$options['union']:''),
$this->parseComment(!empty($options['comment'])?$options['comment']:'')
),$sql);
return $sql;
}
/**
* 获取最近一次查询的sql语句
* @param string $model 模型名
* @access public
* @return string
*/
public function getLastSql($model='') {
return $model?$this->modelSql[$model]:$this->queryStr;
}
/**
* 获取最近插入的ID
* @access public
* @return string
*/
public function getLastInsID() {
return $this->lastInsID;
}
/**
* 获取最近的错误信息
* @access public
* @return string
*/
public function getError() {
return $this->error;
}
/**
* SQL指令安全过滤
* @access public
* @param string $str SQL字符串
* @return string
*/
public function escapeString($str) {
return addslashes($str);
}
/**
* 设置当前操作模型
* @access public
* @param string $model 模型名
* @return void
*/
public function setModel($model){
$this->model = $model;
}
/**
* 析构方法
* @access public
*/
public function __destruct() {
// 释放查询
if ($this->queryID){
$this->free();
}
// 关闭连接
$this->close();
}
// 关闭数据库 由驱动类定义
public function close(){}
}
