Hi I am having this question on how does mapreduce job determine the compress codec on hdfs. From what I read on the definitive guide (page 86)," the CompressionCodecFactory provides a way of mapping a filename extension to a CompressionCodec using its getCodec() method". I did a test with a lzo compressed file without a lzo extension. However, the mapreduce job was still able to get the right codec. Does anyone know why? Thanks in advance.
Jiayu
