K3WISE14.3 固定资产问题

K3wise 14.2 sql2005 2008R2系统
请问下固定资产卡片表T_facard 中Fsource 这个字段是什么意思？干嘛用的呢？
固定资产期末结账的时候update t_fabalance 中的FDeprPeriods（已提折旧期间）有个and Fsource>0 但是新增的卡片，导入的卡片这个字段Fsource都是0

还有就是卡片查询的时候有个已使用期间数或者已使用工作量是从哪张表中取得或者是从哪几张表中加减出来的。麻烦告知下，实在是看不懂语句了:/'(

因为SQL不是很懂（小白），麻烦给解释下！谢谢

语句请看下面：

update t_fabalance set fdeprperiods =a.fdeprperiods+1 from ( select distinct a.fassetid,a.fdeprperiods,a.fdate from t_fabalance a inner join ( select a.* from t_faalter a inner join t_facard b on a.falterid=b.falterid where b.fsource>0 and b.FLifePeriods > b.FPeriodsUsed and FSource in(select FAlterID from t_facard where FAssetNumber = left(b.FAssetNumber,LEN(b.FAssetNumber)-3))) b on a.fassetid=b.fassetid and a.fdate=b.fdate and b.fnew =1 and b.fyear=2018 and b.fperiod=1 ) a where a.fassetid =t_fabalance.fassetid and a.fdate=t_fabalance.fdate and t_fabalance.fhasdepr=0
go
update t_fabalance set FDeprPeriods=b.FDeprPeriods,FOrgValP=b.FOrgValP+b.FOrgValInc-b.FOrgValDec,FDecPreP=b.FDecPreP+b.FDecPreInc-b.FDecPreDec,FAccumDeprP=b.FAccumDeprP+b.FDepr+b.FAccumDeprInc-b.FAccumDeprDec,FNumP=b.FNumP+b.FNumAlter,FYtdOrgValInc=b.FYtdOrgValInc+t_fabalance.FOrgValInc,FYtdOrgValDec=b.FYtdOrgValDec+t_fabalance.FOrgValDec,FYtdDecPreInc=b.FYtdDecPreInc+t_fabalance.FDecPreInc,FYtdDecPreDec=b.FYtdDecPreDec+t_fabalance.FDecPreDec,FYtdDeprInc=b.FYtdDeprInc+t_fabalance.FAccumDeprInc,FYtdDeprDec=b.FYtdDeprDec+t_fabalance.FAccumDeprDec from (select FAssetID,2018 as FYear,2 as FPeriod,FOrgValP,FDecPreP,FOrgvalInc,FOrgValDec,FDecPreInc,FDecPreDec,FNumP,FNumAlter,FAccumDeprP,FAccumDeprInc,FAccumDeprDec,FDepr,FDeprPeriods,FYtdOrgValInc,FYtdOrgValDec,FYtdDecPreInc,FYtdDecPreDec,FYtdDeprInc,FYtdDeprDec from t_fabalance where fcleared<>1 and FYear=2018 and FPeriod=1) b where t_fabalance.FAssetID=b.FAssetID and t_fabalance.FYear=b.FYear and t_fabalance.FPeriod=b.FPeriod
go
insert into t_fabalance (fworkbookid,FAssetID,FYear,FPeriod,FBalID,FCleared,FDate, FNumP,FNumAlter,FOrgValP,FDecPreP,FOrgValInc,FOrgValDec,FDecPreInc,FDecPreDec,FAccumDeprP, FAccumDeprInc,FAccumDeprDec,FWorkload,FDeprShould,FDepr, FDeprShouldLP,FDeprRemain,faltdate,FDeprPeriods,FYtdOrgValInc,FYtdOrgValDec,FYtdDecPreInc,FYtdDecPreDec, FYtdDeprInc,FYtdDeprDec) select fworkbookid,FAssetID,2018 as FYear,2 as FPeriod,7360+FAssetID as FBalID,FCleared,FDate,(FNumP+FNumAlter) as FNumP,0 as FNumAlter, (FOrgValP+FOrgValInc-FOrgValDec) as FOrgValP, (FDecPreP+FDecPreInc-FDecPreDec) as FDecPreP, 0 as FOrgValInc,0 as FOrgValDec, 0 as FDecPreInc,0 as FDecPreDec, (FAccumDeprP+FDepr+FAccumDeprInc-FAccumDeprDec) as FAccumDeprP, 0 as FAcuumDeprInc,0 as FAccumDeprDec, 0 as FWorkload,0 as FDeprShould,0 as FDepr, FDeprShouldLP as FDeprShouldLP,FDeprRemain as FDeprRemain,faltdate, FDeprPeriods as FDeprPeriods, FYtdOrgValInc,FYtdOrgValDec, FYtdDecPreInc,FYtdDecPreDec, FYtdDeprInc,FYtdDeprDec from t_fabalance bal where bal.FYear=2018 and bal.FPeriod=1 and bal.FCleared=0 and not exists (select FBalID from t_fabalance where FAssetID=bal.FAssetID and FYear=2018 and FPeriod=2 and FBalID<=7360)
go