The microarray data files vary in size based on the array types and the format of the data file. A data file in .txt format will only occupy a small amount of space in the Oracle database as compared to at the OS level. But if you choose to perform further normalization of this imported .txt file, you need to remember that the normalized data will also occupy space in the database. Affymetrix data is a little different. When Affymetrix data is saved to the database, ArrayTrack™ not only saves the original cell files as BLOB type, but also saves the converted cel files if the user applies MAS5 (default), RMA, Plier, DChip, etc. It parses the data files into individual records and stores them in the RAW intensity table. If the data is normalized then it is also stored separately. There are indexes that will occupy space as well. So the space required in the ArrayTrack™ database to store all this information about an Affymetrix data file will be significantly (about four times) bigger tha