摘要：转： http://mp.weixin.qq.com/s?__biz=MzAwMDU1MTE1OQ==&mid=2653547609&idx=1&sn=cbb55ee823ddec9d98ef1fa984e001f6&scene=2&srcid=0729T2FQxLgd7RzXuW9hz5dV&fr 阅读全文

摘要：http://db-engines.com/en/system/Memcached%3BMongoDB%3BRedis 阅读全文

摘要：1. mysql http://dev.mysql.com/doc/ 2. postgreSQL https://www.postgresql.org/docs/ 阅读全文

摘要：1. mysql http://dev.mysql.com/doc/refman/5.7/en/insert-on-duplicate.html INSERT ... ON DUPLICATE KEY UPDATE 2. postgrep https://www.postgresql.org/doc 阅读全文