Question

我需要加快这个查询。它需要12秒，返回3917条记录。我的mySQL安装没有针对性能进行调整，也许我需要修改一些配置变量以帮助提高性能。在查询的大部分时间内，查询显示“复制到tmp表”。

此查询用于生成参数搜索的过滤器（即按品牌名称，颜色等过滤搜索结果）。

查询：

SELECT  attributenames.attributeid,
        search_attribute_values.valueid,
        attributenames.name,
        search_attribute_values.value,
        count(search_attribute_values.value) as count,
        search_attribute_values.absolutevalue
    FROM  product
    INNER JOIN  vendorimport
               ON (vendorimport.productid = product.productid
              AND  product.categoryid = 4871)
    INNER JOIN  search_attribute
               ON (search_attribute.productid = product.productid
              AND  search_attribute.localeid = 1)
    INNER JOIN  search_attribute_values
               ON (search_attribute.valueid = search_attribute_values.valueid)
    INNER JOIN  attributenames
               ON (attributenames.attributeid = search_attribute.attributeid
              AND  attributenames.localeid = 1)
    GROUP BY  attributenames.attributeid, search_attribute_values.valueid

说明：

+----+-------------+-------------------------+--------+----------------------------------------------------+----------------------------+---------+---------------------------------------+-------+----------------------------------------------+
| id | select_type | table                   | type   | possible_keys                                      | key                        | key_len | ref                                   | rows  | Extra                                        |
+----+-------------+-------------------------+--------+----------------------------------------------------+----------------------------+---------+---------------------------------------+-------+----------------------------------------------+
|  1 | SIMPLE      | product                 | ref    | PRIMARY,product_categoryID,categoryid_productid    | categoryid_productid       | 4       | const                                 | 38729 | Using index; Using temporary; Using filesort |
|  1 | SIMPLE      | vendorimport            | ref    | productimport_productid                            | productimport_productid    | 5       | microcad.product.productid            |     1 | Using where; Using index                     |
|  1 | SIMPLE      | search_attribute        | ref    | PRIMARY                                            | PRIMARY                    | 8       | microcad.vendorimport.productid,const |     8 | Using where; Using index                     |
|  1 | SIMPLE      | attributenames          | ref    | attributenames_attributeID,attributenames_localeID | attributenames_attributeID | 8       | microcad.search_attribute.attributeid |     4 | Using where                                  |
|  1 | SIMPLE      | search_attribute_values | eq_ref | PRIMARY                                            | PRIMARY                    | 4       | microcad.search_attribute.valueid     |     1 |                                              |
+----+-------------+-------------------------+--------+----------------------------------------------------+----------------------------+---------+---------------------------------------+-------+----------------------------------------------+

架构：

--
-- Table structure for table `attributenames`
--

DROP TABLE IF EXISTS `attributenames`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `attributenames` (
  `attributeid` bigint(20) NOT NULL DEFAULT '0',
  `name` varchar(110) NOT NULL DEFAULT '',
  `localeid` int(11) NOT NULL DEFAULT '0',
  KEY `attributenames_attributeID` (`attributeid`),
  KEY `attributenames_localeID` (`localeid`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

--
-- Table structure for table `product`
--

DROP TABLE IF EXISTS `product`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `product` (
  `productid` int(11) NOT NULL DEFAULT '0',
  `manufacturerid` int(11) NOT NULL DEFAULT '0',
  `isactive` tinyint(1) NOT NULL DEFAULT '1',
  `mfgpartno` varchar(70) NOT NULL DEFAULT '',
  `categoryid` int(11) NOT NULL DEFAULT '0',
  `isaccessory` tinyint(1) NOT NULL DEFAULT '0',
  `equivalency` double NOT NULL DEFAULT '0',
  `creationdate` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
  `modifieddate` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  `lastupdated` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
  PRIMARY KEY (`productid`),
  KEY `product_manufacturerID` (`manufacturerid`),
  KEY `product_categoryID` (`categoryid`),
  KEY `product_mfgPartNo` (`mfgpartno`),
  KEY `categoryid_productid` (`categoryid_productid`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

--
-- Table structure for table `search_attribute`
--

DROP TABLE IF EXISTS `search_attribute`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `search_attribute` (
  `productid` int(11) NOT NULL DEFAULT '0',
  `attributeid` bigint(20) NOT NULL DEFAULT '0',
  `valueid` int(11) NOT NULL DEFAULT '0',
  `localeid` int(11) NOT NULL DEFAULT '0',
  `setnumber` tinyint(2) NOT NULL DEFAULT '0',
  `isactive` tinyint(1) NOT NULL DEFAULT '1',
  PRIMARY KEY (`productid`,`localeid`,`attributeid`,`setnumber`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

--
-- Table structure for table `search_attribute_values`
--

DROP TABLE IF EXISTS `search_attribute_values`;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `search_attribute_values` (
  `valueid` int(11) NOT NULL DEFAULT '0',
  `value` varchar(255) NOT NULL DEFAULT '',
  `absolutevalue` double NOT NULL DEFAULT '0',
  `unitid` int(11) NOT NULL DEFAULT '0',
  `isabsolute` tinyint(1) NOT NULL DEFAULT '0',
  PRIMARY KEY (`valueid`),
  KEY `search_attrval_value` (`value`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

每个表中的记录数：

search_attribute是72,000,000， search_attribute_values是350,000，产品是4,000,000

Answer 1

NULL vs NOT NULL - 使用NOT NULL除非您有NULL的商业原因。

在每个表上使用InnoDB和相关PRIMARY KEY。那可能会更快。

“使用索引”，在有意义的地方，会帮助一些人。

product.categoryid = 4871不属于ON的{{1}}条款;将其移至vendorimport子句。（这不会加快速度。）

您的查询无法进一步优化 - 必须执行所有JOIN并传递所有行。

但是......你真的想要3917行输出吗？你能解决这个问题吗？也许你只需要其中的一些，并可以在SELECT期间过滤它们？这可以加快速度。

慢速mysql查询，使用filesort

1 个答案: