按数字和字符串开头的数字排序SQL服务器表

Question

I'm going to sort an SQL server table by a column having following data:

2.5.1 Sonstiges
1.1.1 Pflegstandards
5.1.7 Arbeitsgemeinschaften
1.2.1 Anforderungen
2.4.5 Betriebsarzt
B Kernprozesse
1.1.1.4 Umgang mit
2.3.3 Kardiologie
......

as you see most of records begin with a number, but there are some starting with string as well. I use following query to cover both cases:

SELECT * from DocumentCategories 
  order by
    case IsNumeric(replace( LEFT(name, CHARINDEX(' ', name)),'.','')) 
        when 0 then name
        when 1 then cast(replace( LEFT(name, CHARINDEX(' ', name)),'.','') as int)
    end

But I get an error regarding varchar to int conversion (because of record containg "B Kernprozesse"). So what's the role of case/when here? Have I missed anything?

I want the output to look something like below:

B Kernprozesse
1.1.1 Pflegstandards
1.2.1 Anforderungen
2.3.3 Kardiologie
2.4.5 Betriebsarzt
2.5.1 Sonstiges
5.1.7 Arbeitsgemeinschaften
1.1.1.4 Umgang mit

......

Answer 1

As mentioned in the comments, you can use TRY_CAST like so:

SELECT * FROM @DocumentCategories 
  ORDER BY
    CASE WHEN TRY_CAST(replace( LEFT(name, CHARINDEX(' ', name)),'.','') AS INT) IS NULL
        THEN 0 
        ELSE cast(replace( LEFT(name, CHARINDEX(' ', name)),'.','') as int) 
    END

If you are in a SQL_SERVER enviornment prior to version 2012, you can use ISNUMERIC and get the same results:

SELECT * FROM @DocumentCategories 
  ORDER BY
    CASE WHEN ISNUMERIC(replace( LEFT(name, CHARINDEX(' ', name)),'.','')) = 0 
        THEN 0 
        ELSE cast(replace( LEFT(name, CHARINDEX(' ', name)),'.','') as int) 
    END 

Here are the results in both cases:

name
=====================
B Kernprozesse
1.1.1 Pflegstandards
1.2.1 Anforderungen
2.3.3 Kardiologie
2.4.5 Betriebsarzt
2.5.1 Sonstiges
5.1.7 Arbeitsgemeinschaften
1.1.1.4 Umgang mit

Answer 2

Are you just looking for

SELECT *
FROM (
      VALUES
      ('2.5.1 Sonstiges'),
      ('1.1.1 Pflegstandards'),
      ('5.1.7 Arbeitsgemeinschaften'),
      ('1.2.1 Anforderungen'),
      ('2.4.5 Betriebsarzt'),
      ('B Kernprozesse'),
      ('1.1.1.4 Umgang mit'),
      ('2.3.3 Kardiologie')
     ) T(Str)
ORDER BY
CASE WHEN TRY_CAST(LEFT(Str, 1) AS INT) IS NOT NULL
     THEN 0
     ELSE 1
END

Which will returns

+-----------------------------+
|             Str             |
+-----------------------------+
| 1.1.1 Pflegstandards        |
| 5.1.7 Arbeitsgemeinschaften |
| 1.2.1 Anforderungen         |
| 2.4.5 Betriebsarzt          |
| 2.3.3 Kardiologie           |
| 1.1.1.4 Umgang mit          |
| 2.5.1 Sonstiges             |
| B Kernprozesse              |
+-----------------------------+

---

UPDATE:

According to the last update of your question, you're looking for

WITH A AS
(
  SELECT *, ((LEN(Str) - LEN(REPLACE(Str, '.', ''))) * 2) + 1 N
  FROM (
        VALUES
        ('2.5.1 Sonstiges'),
        ('1.1.1 Pflegstandards'),
        ('5.1.7 Arbeitsgemeinschaften'),
        ('1.2.1 Anforderungen'),
        ('2.4.5 Betriebsarzt'),
        ('B Kernprozesse'),
        ('1.1.1.4 Umgang mit'),
        ('2.3.3 Kardiologie')
       ) T(Str)
)
SELECT *
FROM A
ORDER BY CASE WHEN TRY_CAST(REPLACE(LEFT(Str, N), '.', '') AS INT) IS NULL
              THEN 0
              ELSE CAST(REPLACE(LEFT(Str, N), '.', '') AS INT)
         END

Returns:

+-----------------------------+---+
|             Str             | N |
+-----------------------------+---+
| B Kernprozesse              | 1 |
| 1.1.1 Pflegstandards        | 5 |
| 1.2.1 Anforderungen         | 5 |
| 2.3.3 Kardiologie           | 5 |
| 2.4.5 Betriebsarzt          | 5 |
| 2.5.1 Sonstiges             | 5 |
| 5.1.7 Arbeitsgemeinschaften | 5 |
| 1.1.1.4 Umgang mit          | 7 |
+-----------------------------+---+

Demo