浮点数计算会出现10.9999999999
我对数据库的金额字段进行加减的操作就会出现
1种是数据拿出来，用php的浮点数算法函数算好再插进去
1种是set money=money-6.4
哪种好
回复内容：
浮点数计算会出现10.9999999999
我对数据库的金额字段进行加减的操作就会出现
1种是数据拿出来，用php的浮点数算法函数算好再插进去
1种是set money=money-6.4
哪种好
金额等数据可以考虑用定点数（DECIMAL）而不是浮点数。
后者更好，因为是原子的。
一般的应用金额只需要2位小数，所以存储时全部乘100即用分保存成整数，这样就能省去很多烦恼。微信支付是这样做的。
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