S4 HANA中的MATDOC和MATDOC_EXTRACT

正文最近做了销售和物料管理方面的一些需求，因此对S/4中的MM的数据模型有了一定的了解。

目前网络已经有一些介绍物料凭证表MATDOC的文章，内容好像不是很详细，另外也没发现介绍库存变更数据表MATDOC_EXTRACT的文章。

我打算把自己知道的一点东西写下来分享。

水平所限，如有不正确的地方，请务必评论指正。

本文将介绍2点内容，以看出区别：MKPF表的replacement object是NSDM_E_MKPF，这个CDS entity是直接从MATDOC中取数的，条件为record_type = 'MDOC'和header_counter = 1，代码如下，可以重点看where语句部分，@AbapCatalog.sqlViewName: 'NSDM_V_MKPF'@bel: 'MKPF Compatibility View'@DataAging.noAgingRestriction: 'false'@ageType.sizeCategory: 'L'@ageType.serviceQuality: #C@ageType.dataClass: #TRANSACTIONAL@ClientHandling.algorithm: #AUTOMATED@AccessControl.authorizationCheck: #NOT_ALLOWED@AbapCatalog.viewEnhancementCategory: #PROJECTION_LISTdefine view nsdm_e_MKPF asselectkey mandt,key mblnr,key mjahr,vgart,blart,blaum,bldat,budat,cpudt,cputm,aedat,usnam,tcode,xblnr,bktxt,frath,frbnr,wever,xabln,awsys,bla2d,tcode2,bfwms,exnum,spe_budat_uhr,spe_budat_zone,le_vbeln,spe_logsys,spe_mdnum_ewm,gts_cusref_no,/*Fields which do belong to APPENDs on MSEG will be provided via EXTEND VIEW to this view. Hence, Industries having also APPENDs can use the same techniqueand just because the alphabetical sequence of APPENDs is also valid for EXTEND VIEW the compability will be ensured.The name of the IS EXTEND VIEW has to be the same as the APPEND. Rules are:ABAP Catalog Objekt: <Append>_VDDL Source <Append>_DDLCDS View = <Append>_EThe alphabetical order of the EXTEND VIEW in the final proxy view is according to the name of sqlViewAppendNameand not accroding to DDL source name or the EXTEND VIEW name! Hence there is still a restriction on 16 chars!*//*DDL sources of known extensions so far:JVMKPF_DDLMILL_MKPF_DDL*/from matdocwhere record_type ='MDOC'and header_counter =1MSEG和它差不多，replacement object是NSDM_E_MSEG，同样从MATDOC中获取数据，条件则只有record_type = 'MDOC'，代码略过不贴。

使用MATDOC代替MKPF和MSEG，可以减少不必要的关联次数。

另外，也有stock_qty和consumption_qty等方便计算的字段，利用它们可以减少相关逻辑处理代码，提高开发速度。

回到顶部库存一些文章提到S4中的库存数据是从MATDOC中实时汇总得出的，的确，MATDOC中包含计算库存所需的全部数据。

但是这个表的数据在物料凭证级别的，随着时间的进行，SAP系统内会积累大量的物料凭证，从这样海量的数据中汇总库存，似乎有些奢侈。

例如FICO模块中的ACDOCA表，就是从年初余额开始汇总，来获取余额的（见前文：S/4 HANA中的ACDOCT和FAGLFLEXT），而不是汇总历史上的通过对各个库存表的replacement object的阅读追踪，我发现实际上库存数据来自于另一个表：MATDOC_EXTRACT。

这是一个实在的透明表，并不存在replacement object：NOTE 2246602 中提到了这个表：为了减轻（从MATDOC中进行聚合运算时因数据量大导致的性能下降的）影响，SAP引入了第二个表MATDOC_EXTRACT，从中计算实际库存数据。

MATDOC_EXTRACT有一小部分来自MATDOC的字段，在物料凭证过账时，每当有数据被插入到MATDOC中，也会有数据被插入MATDOC_EXTRACT中。

MATDOC_EXTRACT里的数据会被定期压缩，比如，假设有以下两条数据：∙Date:20.11.2015; Material:4711; Plant:0001; StorageLocation:0001; StockIdentifier:01; SpecialSto ck:blank; Quantity: 10,0; Unit: PC∙Date:23.11.2015; Material:4711; Plant:0001; StorageLocation:0001; StockIdentifier:01; SpecialSto会被压缩为：Date:PrecompactingDate; Material:4711; Plant:0001; StorageLocation:0001; StockIdentifier:01; S pecialStock:blank; Quantity: 7,0; Unit: PC新的压缩后的数据会被插入MATDOC_EXTRACT，两条被压缩的数据会被从中删除。

通过这种做法，表MATDOC_EXTRACT中的总记录数和用于聚合的记录数都会定期减少，因此，对库存的查询（相比从MATDOC中进行）会有更好的性能。

该过程被称为“预压缩”（precompacting），默认作为期末结算（period end closing）的一部分运行。

如果因此导致期末结算性能下降，也可以自行安排定期后台作业。

以下通过MARD的replacement object，NSDM_E_MARD为例，我们来观察下它是如何从MATDOC_EXTRACT中获取数据的。

源代码：@AbapCatalog.sqlViewName: 'NSDM_V_MARD'@bel: 'MARD Compatibility View'@DataAging.noAgingRestriction: 'false'@ageType.sizeCategory: 'L'@ageType.serviceQuality: #C@ageType.dataClass: #TRANSACTIONAL@ClientHandling.algorithm: #AUTOMATED@AccessControl.authorizationCheck: #NOT_ALLOWED@AbapCatalog.viewEnhancementCategory: #PROJECTION_LISTdefine view nsdm_e_mardas select from mard as tleft outer join nsdm_e_mard_diff as m on t.mandt = m.mandtand t.matnr = m.matnrand t.werks = m.werksand t.lgort = m.lgortassociation [0..1]to E_Productstoragelocation as _ActiveExtension on $projection.matnr = _ActiveExtension.Productand $projection.werks = _ActiveExtension.Plantand $projection.lgort = _ActiveExtension.StorageLocation{key t.mandt,t.pstat,t.lvorm,casewhen m.gjper ='0000000'or m.gjper is null thent.lfgjaelsecast(substring(m.gjper, 1, 4) as abap.numc(4))end as lfgja,casewhen m.gjper ='0000000'or m.gjper is null thent.lfmonelsecast(substring(m.gjper, 6, 2) as abap.numc(2))end as lfmon,t.sperr,case when bst is null then0else bst end as labst, // vvv note 2249780case when m.umlme is null then0else m.umlme end as umlme,case when m.insme is null then0else m.insme end as insme,case when m.einme is null then0else m.einme end as einme,case when m.speme is null then0else m.speme end as speme,case when m.retme is null then0else m.retme end as retme,case when m.vmlab is null then0else m.vmlab end as vmlab,case when m.vmuml is null then0else m.vmuml end as vmuml,case when m.vmins is null then0else m.vmins end as vmins,case when m.vmein is null then0else m.vmein end as vmein,case when m.vmspe is null then0else m.vmspe end as vmspe,case when m.vmret is null then0else m.vmret end as vmret, //^^^ note 2249780t.kzill,t.kzilq,t.kzile,t.kzils,t.kzvll,t.kzvlq,t.kzvle,t.kzvls,t.diskz,t.lsobs,t.lminb,t.lbstf,t.lgpbe,case when m.klabs is null then0else m.klabs end as klabs, // vvv note 2249780case when m.kinsm is null then0else m.kinsm end as kinsm,case when m.keinm is null then0else m.keinm end as keinm,case when m.kspem is null then0else m.kspem end as kspem, //^^^ note 2249780t.dlinl,t.prctl,t.ersda,case when m.vklab is null then0else m.vklab end as vklab, // note 2249780case when m.vkuml is null then0else m.vkuml end as vkuml, // note 2249780t.lwmkb,t.bskrf,'X'as mdrue,t.mdjin,--field added for extensibilityt.dummy_stl_incl_eew_ps,--Fields added for EA-RETAIL(FASHION)t.fsh_salloc_qty_s,case when m./cwm/labst is null then0else m./cwm/labst end as/cwm/labst, //note 2413597 case when m./cwm/insme is null then0else m./cwm/insme end as/cwm/insme, //note 2413597 case when m./cwm/einme is null then0else m./cwm/einme end as/cwm/einme, //note 2413597 case when m./cwm/speme is null then0else m./cwm/speme end as/cwm/speme, //note 2413597 case when m./cwm/retme is null then0else m./cwm/retme end as/cwm/retme, //note 2413597 case when m./cwm/umlme is null then0else m./cwm/umlme end as/cwm/umlme, //note 2413597 case when m./cwm/klabs is null then0else m./cwm/klabs end as/cwm/klabs, //note 2413597 case when m./cwm/kinsm is null then0else m./cwm/kinsm end as/cwm/kinsm, //note 2413597 case when m./cwm/keinm is null then0else m./cwm/keinm end as/cwm/keinm, //note 2413597 case when m./cwm/kspem is null then0else m./cwm/kspem end as/cwm/kspem, //note 2413597 case when m./cwm/vmlab is null then0else m./cwm/vmlab end as/cwm/vmlab, //note 2413597 case when m./cwm/vmins is null then0else m./cwm/vmins end as/cwm/vmins, //note 2413597 case when m./cwm/vmein is null then0else m./cwm/vmein end as/cwm/vmein, //note 2413597 case when m./cwm/vmspe is null then0else m./cwm/vmspe end as/cwm/vmspe, //note 2413597 case when m./cwm/vmret is null then0else m./cwm/vmret end as/cwm/vmret, //note 2413597 case when m./cwm/vmuml is null then0else m./cwm/vmuml end as/cwm/vmuml //note 2413597}可以看到，labst等度量，完全来自于与透明表MARD左连接的CDS entity：nsdm_e_mard_diff，观察这个entity，可以看到，labst等entity其实原本都是stock_qty，只是根据lbbsa字段和sobkz字段的值的不同，被分成不同的度量列。