Three methods for mysql to avoid repeated insertion, and three methods for mysql to insert

Three methods for mysql to avoid repeated insertion, and three methods for mysql to insert

During development, we often encounter this requirement. If the inserted data does not exist, the inserted data will be updated if it exists (Or do not perform any operations.). Mysql insert provides this function and does not need to be processed on our own business logic code. Directly use the functions provided by mysql. Click the following link to view the usage

Http://www.cnblogs.com/zeroone/archive/2012/04/18/2454728.html

Http://www.sifangke.com/2013/05/mysql-insert-sql/