Question

我的MySQL性能有问题。我怎样才能改善它？情况如下：

表“backlogsap”有大约4百万个条目。
创建索引
此表有FK，其他表格有FK到此表=＆gt;不能创建分区。

此查询需要大约140秒才能完成：

select 
    idmaterial,
    materialgroup, 
    materialgroupcategory,
    name,
    dispatchgroup,
    idsupplier, 
    group_concat(distinct sellingorganizationname) as sellingorganizationnames,
    group_concat(distinct idordertype) as idordertypes,
    group_concat(distinct idpositiontype) as idpositiontypes,
    sum(newOrUpdated and isCritical) as classA,
    sum(newOrUpdated and not isCritical) as classB,
    sum(processingstate <3) as classC,

    (select count(innerBacklogsAp.idmaterial) 
        from backlogsap as innerBacklogsAp
        where innerBacklogsAp.idmaterial = src.idmaterial and IsDeleted = 0) as countReplacementVehiclerRequests

from 
    (select 
        backlogsap.idmaterial as idmaterial,
        backlog.processingstate as processingstate,
        material.idsupplier as idsupplier,
        backlogsap.sellingorganizationname as sellingorganizationname,
        backlogsap.idpositiontype as idpositiontype,
        backlogsap.idordertype as idordertype,
        materialindistributioncenter.dispatchgroup as dispatchgroup,
        material.name as name,
        material.idmaterialgroup as materialgroup,
        materialgroup.idmaterialgroupcategory as materialgroupcategory,
        (processingstate = 0 or processingstate = 1) as newOrUpdated,
        ((cancellation.state is not null and cancellation.state = 0 ) or
             (reminderrequest.state is not null and (reminderrequest.state = 2 or reminderrequest.state = 0))
            ) as isCritical
    from backlogsap 
    join backlog using (idbacklogsap)
    left join cancellation using (idcancellation)
    left join reminderrequest on backlog.IdReminderRequest = reminderrequest.idreminder
    left join material using (idmaterial)
    left join materialindistributioncenter using (idmaterial, iddistributioncenter)
    left join materialgroup using (idmaterialgroup)

     where (idcancellation is null or cancellation.State not in (1)) and
         backlogsap.isdeleted = 0 and
         backlogsap.idordertype not in ('ZAP', 'ZAK', 'ZAKO', 'ZAKZ', 'ZAPM') and
         iddistributioncenter = 1469990
    ) as src
group by idmaterial
order by classA desc, classB desc, classC, idmaterial desc

解释

id  select_type         table                           type            possible_keys                                           key                                                                 key_len     ref     rows    Extra
1   PRIMARY             <derived3>                      ALL                                                                                                                                                             26960   Using temporary; Using filesort
3   DERIVED             backlogsap                      index_merge     PRIMARY,fk_BacklogSap_OrderType1_idx,
                                                                        fk_BacklogSap_MaterialInDistributionCenter1_idx,
                                                                        perform_backlogsap_isdeleted,
                                                                        fk_BacklogSap_DistributionCenter_idx                    perform_backlogsap_isdeleted,fk_BacklogSap_DistributionCenter_idx   1,4                 35946   Using intersect(perform_backlogsap_isdeleted,fk_BacklogSap_DistributionCenter_idx); Using where
3   DERIVED             backlog                         eq_ref          idBacklogSAP_UNIQUE,
                                                                        fk_Backlog_BacklogSap1_idx,
                                                                        fk_Backlog_Cancellation1_idx                            idBacklogSAP_UNIQUE                                                 4           ...backlogsap.IdBacklogSap  1   
3   DERIVED             cancellation                    eq_ref          PRIMARY                                                 PRIMARY                                                             4           ...backlog.IdCancellation   1   Using where
3   DERIVED             reminderrequest                 eq_ref          PRIMARY                                                 PRIMARY                                                             4           ...backlog.IdReminderRequest    1   
3   DERIVED             material                        eq_ref          PRIMARY                                                 PRIMARY                                                             45          ...backlogsap.IdMaterial    1   
3   DERIVED             materialindistributioncenter    eq_ref          PRIMARY,
                                                                        unqiue_IdDistributionCenter_IdMaterial,
                                                                        fk_MaterialDistributionCenter_DistributionCenter1_idx,
                                                                        fk_MaterialDistributionCenter_Material1_idx             PRIMARY                                                             49          const,...backlogsap.IdMaterial  1   
3   DERIVED             materialgroup                   eq_ref          PRIMARY                                                 PRIMARY                                                             137         ....material.IdMaterialGroup    1   
2   DEPENDENT SUBQUERY  innerBacklogsAp                 ref             perform_backlogsap_isdeleted,
                                                                        idx_backlogsap_IdMaterial                               idx_backlogsap_IdMaterial                                           45          func    8   Using where

Answer 1

解决：创建组合索引（idmaterial，IsDeleted）

MySQL查询性能提升

1 个答案: