# MATLAB: Reading a large .dat file or some parts of it

Dear All,
I have a very large DAT file (almost 16GB ). It contains the electricity usage of 8000 customers for around 4 years recorded at every 30 minutes (so it has something around 8000*4*365*24*2 rows!)
MS Excel allows me to open this file, however it's obvious that it loads only a part of it. Based on that I could figure out that the format is something like this:
990814, 246745, 0, 2012-07-22 20:00:00, 3.25, 0,0,0,0
which corresponds with:
textscan(SOURCE, FORMAT, COUNT, OPTIONS...)