在 varchar SQL 中添加“-”

Question

我需要从这种格式转换一些字符串：

"1020202020"

到

"1-0-2-0-2-0-2-0-2-0"

我怎样才能以简单的方式做到这一点？

谢谢

Answer 1

每天醒来，我都会想“今天 CTE 会让什么不可能的事情成为可能？”

;with cte as (
    select 
        '1020202020' inputstring,
        convert(varchar(max),'') outputstring
    union all
    select
        substring(inputstring,2,len(inputstring)),
        outputstring + left(inputstring,1) + '-' + case when len(inputstring) = 2 then right(inputstring,1) else '' end
    from cte
    where len(inputstring) > 1
)
select top 1 outputstring from cte order by len(outputstring) desc

Answer 2

您的问题不清楚关于连字符位置的确切规则。 所以，可能会有一些巧妙的方法使用replace()。

对于您的示例字符串：

select replace(replace(col, '02', '-0-2'), '20', '2-0')

Answer 3

我会这样处理：

TRIM(TRAILING "-" FROM REPLACE("10203040", "0", "-0-"))

Answer 4

这是一个非循环/非递归的解决方案。我对 REPLACE() 有一些乐趣，它非常有效。它可以在不到一秒的时间内处理 100,000 行，这可能比任何循环或递归解决方案都要好。

IF OBJECT_ID('strings') IS NOT NULL
    DROP TABLE strings;

CREATE TABLE strings (string BIGINT);

--Populate the table
WHILE(SELECT COUNT(*) FROM strings) < 100000
BEGIN
    INSERT INTO strings
        SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL
        SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL
        SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL
        SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL
        SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000 UNION ALL SELECT RAND() * 10000000000
END

--Add the hyphens with REPLACE() and cut off the extra hyphen at the end with SUBSTRING()
SELECT SUBSTRING(
                REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(REPLACE(string, '0', '0-'),'1','1-'),'2','2-'),'3','3-'),'4','4-'),'5','5-'),'6','6-'),'7','7-'),'8','8-'),'9','9-'),
                0,
                LEN(string)*2
                ) AS String
FROM strings;

缩写结果：

String
------------------------
5-6-1-2-9-4-9-0-8-1
7-5-8-5-1-9-3-0-9
2-2-4-7-6-1-5-7-6-9
9-3-4-6-1-0-3-5-0
9-9-5-3-6-8-8-7-8-9
5-3-7-2-0-5-3-0-6
8-4-0-8-9-8-9-4-5-0
9-8-6-4-6-8-4-4-3-9
6-6-5-8-2-8-7-3-9-2
...