I'm using Data Stage version 11.7 and encountered the error message below from the Lookup stage while compiling the job:
"The supplied expression was empty."
In the Lookup Stage, there are two links from two transformers and there is no common key column between the two datasets.
I googled how to merge or combine the two datasets from two transformers without a common key column. However, I couldn't find a proper way to solve this issue or the way implementing my job in DataStage. Empty Expression
Is there anyone who knows how to solve this problem? If so, please let me know which stage is good for my job or how to solve the error. I would appreciate it.
If you need to join n:m, add a dummy column to each input link and fill it with a constant value like 1. Then join over that column. Decide if mutiple matches result in mutiple output rows or if the first match 'wins' - which would be like a random n:1 then, since every row matches when joining over a const value.
But if you need to join specific rows, it indicates that there actually is a common key but it's not obvious or visible. Either Transform the sources so that they get a common key or use an anchor table that provides the relations. Join that to the first source, then join the second source.
