/*
题目
题目
如何产生1万个编号，插入到表 T(col varchar(20))中，并且不能重复，编号只能从26个小写字母中取 .
*/
--1.当时的写法
select 'a' as col
into #t
union
select 'b' union
select 'c' union
select 'd' union
select 'e' union
select 'f' union
select 'g' union
select 'h' union
select 'i' union
select 'j' union
select 'k' union
select 'l' union
select 'm' union
select 'n' union
select 'o' union
select 'p' union
select 'q' union
select 'r' union
select 's' union
select 't' union
select 'u' union
select 'v' union
select 'w' union
select 'x' union
select 'y' union
select 'z'
insert into T
select top 10000 a.col+b.col+c.col from #t a,#t b ,#t c
drop table #t
--------------------------------------------------------------
--2.看到varchar(20), 想到newid()，再做一些字符串处理
insert into T
select top 10000
replace(replace(replace(replace(replace(replace(replace(replace(replace(replace(lower(left(replace(newid(),
'-', ''), 20)),
'0', 'a'), 1,
'b'), 2, 'c'), 3,
'd'), 4, 'e'), 5,
'f'), 6, 'g'), 7, 'h'), 8, 'i'),
9, 'j') as col
from sys.all_columns ,
sys.all_objects