快速生成基数的辅助表

想生一张26个字母的表,怎样实现。html

能够查看到之前的方法《SQL循环26个字母插入到一个表中https://www.cnblogs.com/insus/archive/2010/12/23/1914346.htmlgit

现在可使用CTE来快速生成:api

;WITH alphabet AS
(
    SELECT 65 AS capital
    UNION ALL
    SELECT capital + 1 FROM alphabet WHERE capital < 90
)
SELECT CHAR(capital) FROM alphabet
Source Code

 

结果以下:ide

 

如想生成数字或其它呢?post

之前的办法《使用CTE生成辅助表(数字或时间)等http://www.javashuo.com/article/p-yyuhzudm-eg.htmlurl

如今解决方案:spa

 

;WITH Digits AS
(
    SELECT 0 AS digit
    UNION ALL
    SELECT digit + 1 FROM Digits where digit < 9
)
SELECT [digit] FROM Digits
Source Code

 

扩展,若是想生成包括10000以内的数字表呢?3d

 

 

;WITH Digits AS
(
    SELECT 0 AS digit
    UNION ALL
    SELECT digit + 1 FROM Digits where digit < 9
)

SELECT kilobit.[digit] * 1000 + hundreds.[digit] * 100 + decade.[digit] * 10 +  unit.[digit] + 1 FROM Digits AS unit
CROSS JOIN  Digits AS decade
CROSS JOIN Digits AS hundreds
CROSS JOIN Digits AS kilobit
Source Code
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