aah, Aries ... I thought WI might be Working Interest ...
guess it is! I have pulled data from Aries before.
I do not know if the fieldname is causing the problem --
just kinda odd to call something that name ;)
lets break apart your equation:
what if [expression] is null?
--> Len([expression]) will be an error
--> InStr(1,[expression]," ") will be an error
--> Left([expression],#) will be an error
what if it doesn't have a space in it?
definitely, if there is no record to even get the field
from, there will be a problem...
Why not make a UDF (User-Defined function) to calculate WI?
What is an example if what [Expression] looks like? Also,
what is the name of a field in the table that will always be
filled out (so we can test if there is a record)? I will
help you with a UDF.
Microsoft Access MVP 2006
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