如“1”转成数字1: var j ='1' var i = +j 最后:i = 1
desc select * from test1 where id='1'; desc select * from test1 where id=10; show warnings \G;
一个数字类型的隐式转换的例子,descselect*fromtest1whereid='1';descselect*fromtest1whereid=10;showwarnings\G;