首页 > 代码库 > 分表分库方法总结

分表分库方法总结

案例一:

1,背景:一个地址薄的应用程序,设计的用户量为2亿,统计出每个用户的地址薄为30个左右,整个数据量为60亿,使用mysql数据库
计划分为:1000个表,100个库 

2,分库分表代码

?
1
2
3
4
5
6
7
8
private function getDbNo($email
    $m = md5($email); 
    $n = hexdec(substr($m, 0, 16)); 
    $tableNo = fmod($n, 1000); 
    $dbNo = $tableNo % 100; 
    return array($dbNo, $tableNo); 

  3,配合的连接访问代码

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
require_once ‘Db/Config.php‘;
 
class Db_Adapter
{
    const MASTER    = 0;
    const SLAVE     = 1;
 
    private static $instances = array();
 
    private $conf = array();
 
    private $conns = array();
 
    private $conn = NULL;
    private $stmt = NULL;
     
    public function __construct($conf)
    {
        $this->conf = $conf;
    }
 
    public function execute($sql, $params)
    {
        $cmd = substr(strtolower(trim($sql)), 0, 6);
        if ($cmd == ‘select‘) {
            $conn = $this->getConn(self::SLAVE);
        } else {
            $conn = $this->getConn(self::MASTER);
        }
 
        $conn->prepare($sql);
        $stmt = $conn->execute($params);
 
        $this->conn = $conn;
        $this->stmt = $stmt;
    }
 
    public function fetch()
    {
        return $this->stmt->fetch();
    }
 
    public function fetchAll()
    {
        return $this->stmt->fetchAll();
    }
 
    public function lastInsertId($name = NULL)
    {
        return $this->conn->lastInsertId($name);
    }
 
    public function rowCount()
    {
        return $this->stmt->rowCount();
    }
 
    private function getConn($type)
    {
        if ($type == self::SLAVE && isset($this->conf[self::SLAVE])) {
            $id = 0;
        } else {
            $id = 1;
        }
 
        if (!isset($this->conns[$id])) {
            $conf = $this->conf[$id];
            $this->conns[$id] = new PDO(
                $conf[‘dsn‘], $conf[‘user‘], $conf[‘pass‘],
                self::dbOptions);
        }
 
        return $this->conns[$id];
    }
 
    public static function getInstance($dbName, $dbNo = 0)
    {
        $key = $dbName . ‘_‘ . $dbNo;
        if (!isset(self::$instances[$key])) {
            $conf = Db_Config::getConfig($dbName, $dbNo); //连接配置参数
            self::$instances[$key] = new self($conf);
        }
 
        return self::$instances[$key];
    }
}

  
4,潜在问题
如果某个表中的那些用户的地址薄联系人超多,如每个人1000个,则可能出现该表超大,需要把该表区分为子表,暂时没有配置中心来处理该情况。
(若真的出现该情况,在连接参数这个地方继续作一次hash)。

转于:http://hanyh.iteye.com/blog/431323

 

 案例二:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
<?php
include ‘config.php‘;
class Model{
        //用户名
        protected $user;
        //密码
        protected $pwd;
        //主机
        protected $host;
        //库名,是一个数组
        protected $dbName=array();
        //字符集
        protected $charset=‘utf8‘;
        //连接资源是一个数组
        protected $_link=array();
        //通用表名
        protected $tabName;
        //真实表名
        protected $trueTabName;
        //表前缀
        protected $prefix;
        //字段缓存
        protected $fields;
        //创建表的sql语句
        protected $createSql=‘CREATE TABLE IF NOT EXISTS __TABLENAME__(
  `id` mediumint(9) NOT NULL AUTO_INCREMENT,
  `username` char(15) NOT NULL,
  `password` char(32) NOT NULL,
  `createtime` int(11) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;‘;
 
//1,通过ID取余,得到真实表名    mod
//2,用户名截取前几位   substr
//3,md5                        md5
//4,不带分库分表        none
 
        protected $partition=array(
                ‘type‘=>‘md5‘,       
                 
                ‘rule‘=>1,
         
        );
 
 
        public function __construct($tabName=‘‘){
                $this->user=DB_USER;
                $this->host=DB_HOST;
                $this->dbName[0]=DB_NAME;
                $this->charset=DB_CHARSET;
                $this->prefix=DB_PREFIX;
                $this->pwd=DB_PWD;
 
                if(empty($tabName)){
                //userModel
                //newModel
                        $this->tabName=$this->prefix.ucfirst(strtolower(substr(get_class($this),0,-5)));
 
                }else{
                        $this->tabName=$this->prefix.$tabName;
                }
 
                $this->_link[0]=$this->connect($this->host,$this->user,$this->pwd,$this->dbName,$this->charset);
 
        }
 
        public function connect($host,$user,$pwd,$dbName,$charset,$linkId=0){
                $conn=mysql_connect($host,$user,$pwd);
 
                 
                if(mysql_errno()){
                        $this->error(-1,$conn);
                        return false;
                }
         
 
                if(!$this->selectDb($dbName[$linkId],$conn)){
                        $this->error(-2,$conn);
                        return false;       
                }
                 
                if(!$this->setCharset($charset,$conn)){
                        $this->error(-3,$conn);
                        return false;
                }
         
 
                return $conn;
 
 
 
        }
 
 
        public function selectDb($dbName,$conn){
                if(mysql_select_db($dbName,$conn)){
 
                        return true;
                }else{
                        return false;
                }       
        }
 
        public function setCharset($charset,$conn){
                if(mysql_set_charset($charset,$conn)){
                        return true;
                }else{
                        return false;
                }
 
        }
 
        public function addServer($host,$user,$pwd,$dbName,$charset,$linkId){
                $this->dbName[$linkId]=$dbName;
                $this->_link[$linkId]=$this->connect($host,$user,$pwd,$dbName,$charset,$linkId);
 
        }
 
        public function getTrueTable($content,$linkId=0){
                switch($this->partition[‘type‘]){
                        case ‘mod‘:
                                if(!is_int($content)){
                                        $this->error(-4);
                                        return false;
                                }
                                $string=$content%$this->partition[‘rule‘];
                                break;
                        case ‘substr‘:
                                $string=substr($content,0,$this->partition[‘rule‘]);
                                break;
                        case ‘md5‘:
                                $string=substr(md5($content),0,$this->partition[‘rule‘]);
                                break;
                        case ‘none‘:
                                $string=null;
                                break;
                }
 
                if(empty($string)){
                        $this->trueTableName=$this->tabName;
 
                }else{
                        $this->trueTableName=$this->tabName.‘_‘.$string;
                }
 
                //第一,判断表是否存在,存在返回表字段缓存
                //第二,不存在,则创建表,返回字段缓存
 
                        $this->existsTable($this->trueTableName,$linkId);
 
 
        }
        //表是否存在
        //是否缓存了字段
 
        protected function existsTable($tableName,$linkId=0){
                $database=$this->dbName[$linkId];
                $sql=‘select `TABLE_NAME` from `INFORMATION_SCHEMA`.`TABLES` where `TABLE_SCHEMA`=\‘‘.$database.‘\‘ and `TABLE_NAME`=\‘‘.$tableName.‘\‘‘;
         
                if($this->execute($sql,$linkId)){
                        //表存在
                        if(file_exists(‘cache/‘.md5($this->tabName).‘.php‘)){
                                $this->fields=include ‘cache/‘.md5($this->tabName).‘.php‘;
                        }else{
                                //暂时留着不写,待会来写
                                $this->fields=$this->getFieldCache($linkId);
                        }
 
                }else{
                        //表不存在
                        $this->createTable($this->trueTableName,$linkId);
                        $this->fields=$this->getFieldCache($linkId);
 
                }
 
        }
 
        protected function getFieldCache($linkId=0){
                if(file_exists(‘cache/‘.md5($this->tabName).‘.php‘)){
                        $fields=include ‘cache/‘.md5($this->tabName).‘.php‘;
                        return $fields;       
                }
                $sql="desc $this->trueTableName";
                $f=$this->query($sql,$linkId);
                 
                $fields=$this->writeFields($f);
 
                return $fields;
                 
 
        }
 
        protected function writeFields($f){
                foreach($f as $key=>$value){
                        $fields[]=$value[‘Field‘];
                         
                        if($value[‘Key‘]==‘PRI‘){
                                $fields[‘_pk‘]=$value[‘Field‘];
                        }
                        if($value[‘Extra‘]==‘auto_increment‘){
                                $fields[‘_auto‘]=$value[‘Field‘];
                        }
                }
                $string="<?php \n return ".var_export($fields,true)."\n?>";
                 
                file_put_contents(‘cache/‘.md5($this->tabName).‘.php‘,$string);
                return $fields;
                         
        }
 
        protected function createTable($tabName,$linkId=0){
                $sql=str_replace(‘__TABLENAME__‘,$tabName,$this->createSql);
         
                $this->execute($sql,$linkId);
        }
 
        //不需要返回结果集我用execute方法
        public function  execute($sql,$linkId=0){
                $conn=$this->_link[$linkId];
         
                $result=mysql_query($sql,$this->_link[$linkId]);
                if($result&&mysql_affected_rows()){
                 
                        return mysql_affected_rows();
                }else{
                        return false;
                }
 
        }
 
 
        //需要返回结果集我用query方法
        public function query($sql,$linkId=0){
                $result=mysql_query($sql,$this->_link[$linkId]);
                 
                if($result&&mysql_affected_rows()){
                        while($row=mysql_fetch_assoc($result)){
 
                                $rows[]=$row;
                        }
                }else{
                        return false;
                }
                return $rows;
        }
 
 
        public function error($num,$conn){
                switch($num){
                        case -1:
                                $string=‘连接数据库服务器失败‘.mysql_error($conn);
                                break;
                        case -2:
                                $string=‘选择数据失败‘;
                                break;
                        case -3:
                                $string=‘设置字符集失败‘;
                                break;
                        case -4:
                                $string=‘数据库路由时选择的是取余,传入的不是整型‘;
                                break;
                }
        }
 
         
 
 
        //查最大值
        public function max($field,$linkId=0){
                if(!in_array($field,$this->fields)){
                        return false;
                }
                $sql="select max($field) as re from $this->trueTableName";
                $result=$this->query($sql,$linkId);
                $row=$result[‘re‘];
                return $row;
                 
 
        }       
 
         
 
        //查最小值
        public function min($field,$linkId=0){
                if(!in_array($field,$this->fields)){
                        return false;
                }
                $sql="select min($field) as re from $this->trueTableName";
                $result=$this->query($sql,$linkId);
                $row=$result[‘re‘];
                return $row;
                 
 
        }
        //求和
        public function sum($field,$linkId=0){
                if(!in_array($field,$this->fields)){
                        return false;
                }
                $sql="select sum($field) as re from $this->trueTableName";
                $result=$this->query($sql,$linkId);
                $row=$result[‘re‘];
                return $row;
                 
 
        }
        //最平均数
        public function avg($field,$linkId=0){
                if(!in_array($field,$this->fields)){
                        return false;
                }
                $sql="select avg($field) as re from $this->trueTableName";
                $result=$this->query($sql,$linkId);
                $row=$result[‘re‘];
                return $row;
                 
 
        }
        //求总数
        public function count($field=‘‘,$linkId=0){
                if(empty($field)){
                        $field=$this->fields[‘_pk‘];
                }
                $sql="select count($field) as re from $this->trueTableName";
                $result=$this->query($sql,$linkId);
                $row=$result[‘re‘];
                return $row;
        }
        //
        //删除
        public function delete($data,$where=‘‘,$linkId=0,$order=‘‘,$limit=‘‘){
                //delete from 表  where 字段  order by  字段 limit
                 
                if(is_array($data)){
                        $value=join(‘,‘,$data);
                }else{
                        $value=(int)$data;
                }
                $fields=$this->fields[‘_pk‘];
 
                if(empty($where)){
 
                        $sql="delete from $this->trueTableName where $fields in ($value)";
                }else{
                        $where=‘where ‘.$where;
                        if(!empty($order)){
                                $order=‘order by ‘.$order;       
                        }
                        if(!empty($limit)){
                                $limit=‘limit ‘.$limit;       
                        }
 
                        $sql="delete from $this->trueTableName $where $order $limit";
                }
                return $this->execute($sql,$linkId);
        }
        //
        //修改
        public function save($data,$where,$linkId=0,$order=‘‘,$limit=‘‘){
 
                //update 表  set 字段=值,字段=值 where 条件 order  limit
                $key=array_keys($data);
                $newKey=array_intersect($key,$this->fields);
         
                foreach($data as $key=>$value){
                        if(!in_array($key,$newKey))
                                continue;
                        $update.=$key.‘="‘.$value.‘",‘;
                 
                }
                $update=rtrim($update,‘,‘);
                 
                if(!empty($order)){
                        $order=‘order by ‘.$order;
                }
                if(!empty($limit)){
                        $limit=‘limit ‘.$limit;
                }
 
                if(!empty($where)){
                        $where=‘where ‘.$where;
                }
 
 
                $sql="update $this->trueTableName set $update $where $order $limit";
 
                echo $sql;
                $result=$this->execute($sql,$linkId);
                return $result;
 
        }
 
 
 
        //增加
        public function add($data,$linkId=0){
                //insert into 表(字段) values(值)
                $key=array_keys($data);
                $newKey=array_intersect($key,$this->fields);
                foreach($data as $key=>$value){
                        if(!in_array($key,$newKey))
                                continue;
                        $values.="‘".$value."‘,";
                }
                $values=trim($values,‘,‘);
                $fields=join(‘,‘,$newKey);
                $sql="insert into $this->trueTableName($fields) values($values)";
                echo $sql;
                $result=$this->execute($sql,$linkId);
                return $result;
        }
 
 
        //单条查询
        public function find($linkId=0,$where=‘‘,$order=‘‘){
                //select * from 表 where  order  limit 1
                $field=join(‘,‘,$this->fields);
                if(!empty($where)){
                        $where=‘where ‘.$where;
                }
                if(!empty($order)){
                        $order=‘order by ‘.$order;
                }
                $sql="select $field from $this->trueTableName $where $order limit 1";
                $result=$this->query($sql,$linkId);
                return $result[0];
                 
        }
 
        //多条查询
        public function select($field=‘‘,$linkId=0,$where=‘‘,$order=‘‘,$limit=‘‘){
                //select * from 表 where  order  limit
                if(empty($field)){
                        $fields=join(‘,‘,$this->fields);
                }else{
                        if(is_array($field)){
                                $newKey=array_intersect($field,$this->fields);
                                $fields=implode(‘,‘,$newKey);
                        }else{
                                $fields=$field;
                        }
                }
                if(!empty($where)){
                        $where=‘where ‘.$where;
                }
                if(!empty($order)){
                        $order=‘order by ‘.$order;
                }
                if(!empty($limit)){
                        $limit=‘limit ‘.$limit;
                }
                $sql="select $fields from $this->trueTableName $where $order $limit";
                $result=$this->query($sql,$linkId);
                return $result;
                 
        }
        //按照字段来查询数据
 
 
        function __call($name,$param){
                $key=substr($name,0,5);
                if(strtolower($key)==‘getby‘){
                        $field=strtolower(substr($name,5));
                 
                        if(!in_array($field,$this->fields)){
                                return false;
                        }
                        $f=join(‘,‘,$this->fields);
                        $value=$param[0];
                        $sql="select $f  from $this->trueTableName where $field=‘$value‘";
         
                        $result=$this->query($sql);
                        return $result[0];
 
                }
        }
 
 
 
}
 
?>