在TSQL中生成隨機中間初始值

Question

如何在TSQL中編寫程序來遍歷表的每一行併爲中間初始列生成一個隨機字母？

Answer 1

您可以使用簡單的UPDATE語句，而不是爲它編寫程序。一個例子是（使用你的答案中的表/字段名稱）;

UPDATE Contact SET conMName = CHAR(ABS(CHECKSUM(NEWID()))%26+65) 

Answer 2

假設您的Identity列保存的整數加1，那麼標識列稱爲conID，您的表稱爲EDI.Contact，並且中間名稱的列稱爲conMName，以下代碼可以工作;

DECLARE 
    @Counter INT = '1' 
    , @GeneratedLetter CHAR(1) 
    , @NumberOfRows INT = (SELECT COUNT(*) FROM EDI.Contact) -- Replace with your table name 
    , @LetterNumber INT 
WHILE (@Counter < @NumberOfRows +1) 
BEGIN 
SET @LetterNumber = (CAST(RAND(CHECKSUM(NEWID())) * 26 as INT) + 1) 
IF @LetterNumber = '1' 
SET @GeneratedLetter = 'A' 
ELSE IF @LetterNumber = '2' 
SET @GeneratedLetter = 'B' 
ELSE IF @LetterNumber = '3' 
SET @GeneratedLetter = 'C' 
ELSE IF @LetterNumber = '4' 
SET @GeneratedLetter = 'D' 
ELSE IF @LetterNumber = '5' 
SET @GeneratedLetter = 'E' 
ELSE IF @LetterNumber = '6' 
SET @GeneratedLetter = 'F' 
ELSE IF @LetterNumber = '7' 
SET @GeneratedLetter = 'G' 
ELSE IF @LetterNumber = '8' 
SET @GeneratedLetter = 'H' 
ELSE IF @LetterNumber = '9' 
SET @GeneratedLetter = 'I' 
ELSE IF @LetterNumber = '10' 
SET @GeneratedLetter = 'J' 
ELSE IF @LetterNumber = '11' 
SET @GeneratedLetter = 'K' 
ELSE IF @LetterNumber = '12' 
SET @GeneratedLetter = 'L' 
ELSE IF @LetterNumber = '13' 
SET @GeneratedLetter = 'M' 
ELSE IF @LetterNumber = '14' 
SET @GeneratedLetter = 'N' 
ELSE IF @LetterNumber = '15' 
SET @GeneratedLetter = 'O' 
ELSE IF @LetterNumber = '16' 
SET @GeneratedLetter = 'P' 
ELSE IF @LetterNumber = '17' 
SET @GeneratedLetter = 'Q' 
ELSE IF @LetterNumber = '18' 
SET @GeneratedLetter = 'R' 
ELSE IF @LetterNumber = '19' 
SET @GeneratedLetter = 'S' 
ELSE IF @LetterNumber = '20' 
SET @GeneratedLetter = 'T' 
ELSE IF @LetterNumber = '21' 
SET @GeneratedLetter = 'U' 
ELSE IF @LetterNumber = '22' 
SET @GeneratedLetter = 'V' 
ELSE IF @LetterNumber = '23' 
SET @GeneratedLetter = 'W' 
ELSE IF @LetterNumber = '24' 
SET @GeneratedLetter = 'X' 
ELSE IF @LetterNumber = '25' 
SET @GeneratedLetter = 'Y' 
ELSE IF @LetterNumber = '26' 
SET @GeneratedLetter = 'Z' 
UPDATE EDI.Contact -- Replace with your table name 
SET conMName = @GeneratedLetter -- Replace with column that holds middle names 
WHERE conId = @Counter -- Replace with identity column name 
SET @Counter = (@Counter + 1) 
END