大衛的部落格

MS SQL的DATETIME精度只有1/300秒, 因此毫秒的個位數只會看到0、3、7，也就是x.xx0、x.xx3、x.xx7.不在這3個範圍的都會被自動捨入到接近的值。以下是測試的情況:
SELECT CAST('2021-12-31 23:59:59.990' AS DATETIME)-->2021-12-31 23:59:59.990
SELECT CAST('2021-12-31 23:59:59.991' AS DATETIME)-->2021-12-31 23:59:59.990
SELECT CAST('2021-12-31 23:59:59.992' AS DATETIME)-->2021-12-31 23:59:59.993
SELECT CAST('2021-12-31 23:59:59.993' AS DATETIME)-->2021-12-31 23:59:59.993
SELECT CAST('2021-12-31 23:59:59.994' AS DATETIME)-->2021-12-31 23:59:59.993
SELECT CAST('2021-12-31 23:59:59.995' AS DATETIME)-->2021-12-31 23:59:59.997
SELECT CAST('2021-12-31 23:59:59.996' AS DATETIME)-->2021-12-31 23:59:59.997
SELECT CAST('2021-12-31 23:59:59.997' AS DATETIME)-->2021-12-31 23:59:59.997
SELECT CAST('2021-12-31 23:59:59.998' AS DATETIME)-->2021-12-31 23:59:59.997
SELECT CAST('2021-12-31 23:59:59.999' AS DATETIME)-->2022-01-01 00:00:00.000

首先打開安裝好的Microsoft SQL Server Management Studio連上資料庫，然後進入已經建好的資料庫中,對資料庫選單中的"可程式性"-->"預存程序"點滑鼠右鍵，選擇"新增預存程序",相關畫面如下圖一:
(圖一)