随记 MySql 带正负的随机数

SELECT RAND() -- 随机数(小数): 0.785456465787789798789
SELECT RAND()*10 -- 随机数(大于0) : 1.781432146589789
SELECT ROUND(RAND()*10,0) -- 随机正整数(大于0) :0 到 9
SELECT ROUND(rand () *10-5,0) -- 随机正负整数: -5 到 5
SELECT ROUND(rand () *20-10,0) -- 随机正负整数: -10 到 10


举例(将数据随机调整 ±5):

SELECT id
,Temperature+ROUND(rand() *10-5,0) as Temperature
,Humidity +ROUND(rand() *10-5,0)  as Humidity

FROM tb_tem_hum

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转载自blog.csdn.net/djk8888/article/details/141197089