Can you set a join to compare two fields of a different length

[#1]

I am trying to compare the Reference Doc and Item on the delivery item to the Purchase Order Item table

LIPS~VGBEL = EKPO~EBELN and LIPS~VGPOS = EKPO-EBELP

VGPOS is 6 positions but EBELP is 5.   

[Gysbert_Wassenaar]

Depends on the content of the fields. Are they numbers or alphanumeric? Can you post some example data?

[#3]

could you please attach an example?

[#4]

Here is an example

[#5]

I am still having no luck comparing a 6 position field to a 5 position field.    How can a strip off the 6 position to make it 5 so the compare will work?

Issue is that the item field in most tables in SAP is 6 positions, but in the Purchasing Item table it is only 5 positions.