改善 Programmer 生活的SQL 技巧
REF:
http://sqlfiddle.com/#!2/fbf31/5/0
http://wiki.postgresql.org/wiki/Foreign_data_wrappers
DEMO DB
Host ec2-107-20-224-218.compute-1.amazonaws.com
Database dbkrqa4hb2ckgl
User qzacwszmuccqrc
Port 5432
Password SByaWWQCEiCYqwNAfl8iwCmqPa