想生一张26个字母的表,怎样实现。
可以查看到以前的方法《SQL循环26个字母插入到一个表中》https://www.cnblogs.com/insus/archive/2010/12/23/1914346.html
如今可以使用CTE来快速生成:
;WITH alphabet AS ( SELECT 65 AS capital UNION ALL SELECT capital + 1 FROM alphabet WHERE capital < 90 ) SELECT CHAR(capital) FROM alphabet
结果如下:
如想生成数字或其它呢?
以前的办法《使用CTE生成辅助表(数字或时间)等》https://www.cnblogs.com/insus/p/10891965.html
现在解决方案:
;WITH Digits AS ( SELECT 0 AS digit UNION ALL SELECT digit + 1 FROM Digits where digit < 9 ) SELECT [digit] FROM Digits
扩展,如果想生成包括10000之内的数字表呢?
;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