有些時候我們需要客製化程式去處理BOM的結構資料，然後檢核失效日(VALID_TO)。但是在STPO這張TABLE中只有記錄VALID_FROM(DATUV)，這時候可以試著利用STAS來搭配STPO一起處理。
STAS~LEKEZ這欄位如果是'X'，那就代表預計失效，這時候它的VALID_FROM(DATUV)就代表的預計失效的日期。
有STAS~STLNR(BOM表頭key)、STAS~STLKN(Component key)與STAS~AENNR(Changer no.)就可以找到對應STPO的資訊，搭配STPO~IDNRK就可以找到要檢核的Component的VALIE_TO。
Sometime we need to check BOM component's VALID_TO, but in table STOP just only has filed VALID_FROM. So, we can join table STAS, use keys STAS~STLKN(bom header), STAS~STLKN(bom component) and STAS~AENNR(change no, option) to join STPO, then use STPO~IDNRK to search the component you want and final STAS~LEKEZ = 'X' means the component will be removed. In such case, STAS~DATUV means, when will the component be remove.
now you can get the component's valid to.
