Data pulling from MARD, MARC etc. - Which table first I hv to use?

Question

Hi Experts,
User enters the Matnr, plant, storage location inputs in the selections.
It is need to get the corresponding data from MARD, MARC, MDBS, VBBE.
So,
1) Is it possible that, suppose MARD having 10 matnrs, where as MARC is having 15, where as MDBS have only 7? or every table does hv 10 definately?
2) as I need to pull the data from these tables, pls. suggest me, in which order I hv to pull, I mean, first from Which table i hv to pull, and as second, wht is next table? for more reliability.
thanq

Answer 1

HI
select matnr
          LBSTF
   from mard
into table itab1
where matnr = p_matnr
condition.
if not itab[] is initial.
select EISBE
     from marc
  into table itab1
for all entries in itab
where matnr = itab-matnr
and any other condition
select MENGE
      from MDBS
  into table itab2
for all entries in itab1
where matnr = itab1-matnr condition
endif.
write like this
you will get data if availble