thinkphp3.1DB.class.php关于切换数据库bug问题，今天再切换第四个数据库是怎么都切换不了，于是发现是DB.class.php 文件有个bug，现在已经修复。

// +----------------------------------------------------------------------/** * ThinkPHP 数据库中间层实现类 * @category Think * @package Think * @subpackage Core * @author liu21st */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 = '
'
;
protected $multiConfig = [];
// 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%'
;
// 参数绑定 protected $bind = array();
/** * 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) {
if(empty($this->multiConfig)) {
// 缓存分布式数据库配置解析 foreach ($this->config as $key=>$val){
$this->multiConfig[$key] = explode('
,'
,$val);
}
}
$_config = $this->multiConfig;
// 数据库读写是否分离 if(C('
DB_RW_SEPARATE'
)){
// 主从式采用读写分离 if($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){
if(is_array($val) && '
exp'
== $val[0]){
$set[] = $this->parseKey($key).'
='
.$val[1];
}
elseif(is_scalar($val) || is_null(($val))) {
// 过滤非标量数据 if(C('
DB_BIND_PARAM'
) && 0 !== strpos($val,'
:'
)){
$name = md5($key);
$set[] = $this->parseKey($key).'
=:'
.$name;
$this->bindParam($name,$val);
}
else{
$set[] = $this->parseKey($key).'
='
.$this->parseValue($val);
}
}
}
return '
SET '
.implode('
,'
,$set);
}
/** * 参数绑定 * @access protected * @param string $name 绑定参数名 * @param mixed $value 绑定值 * @return void */ protected function bindParam($name,$value){
$this->bind['
:'
.$name] = $value;
}
/** * 参数绑定分析 * @access protected * @param array $bind * @return array */ protected function parseBind($bind){
$bind = array_merge($this->bind,$bind);
$this->bind = array();
return $bind;
}
/** * 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){
$whereStr .= '
( '
;
if(is_numeric($key)){
$key = '
_complex'
;
}
if(0===strpos($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 $whereStr = is_string($val)? $val : substr($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 $joinStr = preg_replace_callback("/__([A-Z_-]+)__/sU",function($matches){
return C("DB_PREFIX").".".strtolower($matches[1]);
}
,$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){
if(is_array($val) && '
exp'
== $val[0]){
$fields[] = $this->parseKey($key);
$values[] = $val[1];
}
elseif(is_scalar($val) || is_null(($val))) {
// 过滤非标量数据 $fields[] = $this->parseKey($key);
if(C('
DB_BIND_PARAM'
) && 0 !== strpos($val,'
:'
)){
$name = md5($key);
$values[] = '
:'
.$name;
$this->bindParam($name,$val);
}
else{
$values[] = $this->parseValue($val);
}
}
}
$sql = ($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,$this->parseBind(!empty($options['
bind'
])?$options['
bind'
]:array()));
}
/** * 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,$this->parseBind(!empty($options['
bind'
])?$options['
bind'
]:array()));
}
/** * 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,$this->parseBind(!empty($options['
bind'
])?$options['
bind'
]:array()));
}
/** * 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,$this->parseBind(!empty($options['
bind'
])?$options['
bind'
]:array()));
}
/** * 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,$this->parseBind(!empty($options['
bind'
])?$options['
bind'
]:array()));
if($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(){
}
}