big data
Volume
Velocity
Value
Variety
Veracity

Structure, semi-structure and unstructured data
Organized(rdbms), partialy organized, no formal structure(xml, json) and unorganized no dsta schema(multimedia files)

Difference between hadoop and rdbms
rdbms relies on structure data, provides limited or no processing reads fast schema is already known, suitable for transaccion processing
hadoop can store any kind of data, process data in distributeed parallel fashion, writes fast, suitable for online analytical processing

Components of hadoop?
HDFS - > YARN (yet another resource negotiator)
NameNode -> Resource Manager (master)
DataNode -> Node Manager (slave)

Main hadoop configuration files
hadoop-env.sh
core-site.xml
hdfs-site.xml
yarn-site.xml
mapred-site.xml
masters
slaves


What is the problem of having lots of small files? How it can be solved?




I have always enjoyed working with Java related technologies, I have plenty of Java development and architecture experience, including 3 Java Certifications
Quality is the core of everything I do