Reported for version 10
What are the limitations for the number of items in a lookup?
The best practice with lookups is that they should fit into memory. Note, that the lookups are not kept inside the memory of DQC process, but in cached memory, i.e., you cannot control the size via
-Xmx parameter in DQC. Lookups use the free memory of the machine. This means that they may be thrown away by other processes on the machine that would like to consume cached (free) memory.