SQL error when exporting

Ok guys,

weird scenario: here's my example.

Select A, B, D
From Table1
Where Include=Yes;


Now, the table is setup so, such that, A is followed by b, c, d, etc. I get an error that says "Item not found" when calling for D. It seems to be because i skipped c. If I call C, it works fine.

I hope this example is clear enough to get my point across. Any suggestions? Thanks.