This is the 3rd course in big data specification courses.
Data model reivew
1, data model 的特点： Structured， operations on it, constrains.
2. different types of data model
Retrieving data (week 1/2)
Querying data from ralational DB.
query data from mongodb
输出如下，注意第3条记录 
Big data integration (week3)
infomation integration 就是从多个infomation source 取数据来完成一个task
big data 主要的问题是 many sources, 两个solution 是pay-as-you-go, probabilistic schema mapping.
probabilitistic schema mapping 感觉是一种自动计算出 integration schema 的方法.
Industry examples for big data integration and processing
using Splunk and Datameer(used in digital music industry)