MySQL垂直分表

业务表增长速度较快，单表数据较大，对表的读写有影响。
思路：化整为零，把单表拆解为多表，按指定规则选择表

以Laravel项目为例，分表读取代码如下： public function changeTable($companyId) {     // 分表算法，根据companyId选择分表，请勿修改算法，以免混淆分表数据     $posfix = intval($companyId) % 10;     $tableName = $posfix ? "demo_$posfix" : 'demo';     return $this->setTable($tableName); }  调用方法： public function countCompanyData($companyId, $condition) {     return $this->changeTable($companyId)->multiwhere($condition)->count(); }  算法实现后，就差表数据迁移了  步骤一，先执行 SHOW CREATE TABLE `demo`; 得到原始表的创建语句，然后，加个下标，就是分表的创建语句了  步骤二，创建所需要的所有分表，需要创建 1~9 编号的分表，这里以编号1为例 CREATE TABLE `demo_1` (   `id` int(10) unsigned NOT NULL AUTO_INCREMENT COMMENT '主键ID',   `company_id` int(11) unsigned NOT NULL COMMENT '商家ID',   `content` varchar(255) NOT NULL COMMENT '短信内容',   `phone` varchar(11) NOT NULL COMMENT '手机号'   PRIMARY KEY (`id`),   KEY `company_id` (`company_id`),   KEY `Phone` (`phone`,`company_id`), ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='演示表';  步骤三，创建好分表后，执行迁移语句 INSERT INTO `demo_1` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 1; INSERT INTO `demo_2` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 2; INSERT INTO `demo_3` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 3; INSERT INTO `demo_4` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 4; INSERT INTO `demo_5` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 5; INSERT INTO `demo_6` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 6; INSERT INTO `demo_7` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 7; INSERT INTO `demo_8` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 8; INSERT INTO `demo_9` SELECT * FROM `demo` WHERE MOD(`company_id`, 10) = 9;  步骤四，备份原始表（demo表）的数据  步骤五，删除已迁移的数据，留下属于 编号0 表的数据 DELETE FROM `demo` WHERE MOD(`company_id`, 10) != 0;  P.S：修改后所有的SQL操作，都应该含有 company_id 信息，这样才能找到具体的分表。  如果业务中有和company_id无关的汇总类的查询，已统计所有记录为例，那么可以  public function countTable($condition) {     $posfixList = range(0, 9);     $sum = 0;     foreach ($posfixList as $posfix) {         $tableName = $posfix ? "demo_$posfix" : 'demo' ;         $count = $this->setTable($tableName)->multiwhere($condition)->sum('id');     }     $sum += $count;     return $sum; }  

来源：博客园

作者：Funsion Wu

链接：https://www.cnblogs.com/funsion/p/11424703.html