sql server 產生隨機數 rand函數

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https://docs.microsoft.com/en-us/sql/t-sql/functions/rand-transact-sql?view=sql-server-2017

在某一個區間內產生隨機數

https://stackoverflow.com/questions/7878287/generate-random-int-value-from-3-to-6

原理，rand函數會產生一個在0到1之間的隨機float數。

用這個隨機數*區間範圍+最小值，就得到一個區間範圍內的隨機數。然後用round函數去掉小數點後面的。

DECLARE @Random INT;DECLARE @Upper INT;DECLARE @Lower INTSET @Lower = 3 ---- The lowest random numberSET @Upper = 7 ---- One more than the highest random numberSELECT @Random = ROUND(((@Upper - @Lower -1) * RAND() + @Lower), 0)SELECT @Random

 

 

產生布爾值

https://stackoverflow.com/questions/20597269/how-to-generate-random-boolean-value-in-sql-server-2008

If you are only generating one row, you could use something as simple as:

SELECT CAST(ROUND(RAND(),0) AS BIT)

However, if you are generating more than one row, RAND() will evaluate to the same value for every row, so please see Martin Smith‘s answer.

 

sql server 產生隨機數 rand函數