Endianess always comes up when migrating applications and databases from RISC to x86. The issue is often time overblown as if you are running on a relational database the database vendor will provide tools or automated methods to convert the data properly. Oracle RMAN is often the first choice. Oracle imp/exp, data pump, and GoldenGate can also be used.
A bigger issue would be applications that access OS files. These OS files will need to be converted from big endian (RISC) to little endian (CISC) and then the application may be impacted because of the endianess differences.