SQL 字符串按逗号和空格分割

Question

我想将data 列拆分为 3 个新列

1. 最后一个
2. 第一
3. 发帖

数据的值带有空格或“,”逗号分隔。

data
ABC, RICK SEAN, MD
MES, AEL B, MD FACC
DAN, RK, MD
OHI, NIK, MD F
KA E SYME, PA-C
ALL MUD, SIM, MD
RINE EEMAN, FNP-C
ABC, PQR DIR

所需输出：

desc                        last        first       post

ABC, RICK SEAN, MD          ABC         RICK SEAN   MD          
MES, AEL B, MD FACC         MES         AEL B       MD FACC
DAN, RK, MD                 DAN         RK          MD
OHI, NIK, MD F              OHI         NIK         MD F
KA E SYME, PA-C             KA          E SYME      PA-C
ALL MUD, SIM, MD            ALL MUD     SIM         MD
RINE EEMAN, FNP-C           RINE        EEMAN       FNP-C
ABC, PQR DIR                ABC         PQR         DIR

检查第一行数据列有2个逗号，最后一行只有一个逗号。

这里创建的示例http://rextester.com/BEHUP42399

select left(data, charindex(',', data) -1)  from TTT

它尝试了“姓氏”列，但为“KA E SYME”给出了错误的 o/p，即单逗号记录。 如果数据只有一个逗号，而逗号之前只有一个单词，则表示逗号之后有两个单词，那么结果将是。检查最后记录 ABVC。

eg. ABC, PQR DIR                

Answer 1

您可以使用CROSS APLLY 进行尝试：

    SELECT N.DATA [descr],
       CASE
           WHEN N.last = ''
           THEN LTRIM(N.first)
           ELSE LTRIM(N.last)
       END last,
       CASE
           WHEN N.last = ''
           THEN SUBSTRING(LTRIM(N.post), 1, CHARINDEX(CHAR(32), LTRIM(N.post)))
           ELSE LTRIM(N.first)
       END first,
       CASE
           WHEN N.last = ''
           THEN SUBSTRING(LTRIM(N.post), (CHARINDEX(' ', LTRIM(N.post))+1), LEN(LTRIM(N.post)))
           ELSE LTRIM(N.post)
       END post
FROM
(
    SELECT D.DATA,
           CASE
               WHEN D.post IS NULL
               THEN LEFT(D.last, CHARINDEX(' ', D.last))
               ELSE D.last
           END last,
           CASE
               WHEN d.post IS NULL
               THEN SUBSTRING(D.last, (CHARINDEX(' ', D.last)+1), LEN(D.last))
               ELSE d.first
           END first,
           CASE
               WHEN D.post IS NULL
               THEN d.first
               ELSE d.post
           END post
    FROM
    (
        SELECT DISTINCT
               DATA,
               Split.a.value('/M[1]', 'NVARCHAR(MAX)') last,
               Split.a.value('/M[2]', 'NVARCHAR(MAX)') first,
               Split.a.value('/M[3]', 'NVARCHAR(MAX)') post
        FROM
        (
            SELECT DATA,
                   CAST('<M>'+REPLACE(DATA, ',', '</M><M>')+'</M>' AS XML) AS String
            FROM #TM
        ) A
        CROSS APPLY String.nodes('/M') Split(a)
    ) D
) N;

期望的结果：

desc                        last        first       post

ABC, RICK SEAN, MD          ABC         RICK SEAN   MD          
MES, AEL B, MD FACC         MES         AEL B       MD FACC
DAN, RK, MD                 DAN         RK          MD
OHI, NIK, MD F              OHI         NIK         MD F
KA E SYME, PA-C             KA          E SYME      PA-C
ALL MUD, SIM, MD            ALL MUD     SIM         MD
RINE EEMAN, FNP-C           RINE        EEMAN       FNP-C
ABC, PQR DIR                ABC         PQR         DIR

注意：以上结果以提供的数据为准。

Answer 2

您可以尝试如下查询

逻辑是我们找到逗号的数量，并在逗号小于 3 时为第一个出现的空格添加逗号 这也适用于字符串中根本没有逗号的情况。

create table staging_tbl_single_row (data varchar(max))
insert into staging_tbl_single_row values
('ABC, RICK SEAN, MD')
,('MES, AEL B, MD FACC')
,('DAN, RK, MD')
,('OHI, NIK, MD F')
,('KA E SYME, PA-C')
,('ALL MUD, SIM, MD')
,('RINE EEMAN, FNP-C'),
('ABC, PQR DIR');

; with cte as 
(
 select 
    row_number() over (order by (select NULL)) as column1,
    column2=
    case
        when 
             (len(data)-len(replace(data,',',''))=2) 
        then 
             data 
        when 
             (len(data)-len(replace(data,',',''))=1) 
        then 
             case --check if space is to the left of comma
                    when 
                        charindex(' ',left(data, charindex(',',data)))<>0
                    then 
                        stuff(data,charindex(' ',data),1,',')
                    else 
                        left(data, charindex(',',data))+
                        stuff(
                            substring(data,
                                      charindex(',',data)+1,
                                      len(data)
                                     ),
                            charindex(' ',
                                      substring(
                                          data,
                                          charindex(',',data)+1,
                                          len(data)
                                          ),
                                      2)
                            ,1,',')
                    end

       when
            (len(data)-len(replace(data,',',''))=0)
        then
              stuff(
       stuff(data,charindex(' ',data),1,',')
        ,charindex(' ',stuff(data,charindex(' ',data),1,','))
       ,1,',')

    end,data
    from 
    staging_tbl_single_row
)

select 
    last=[1],first=[2],post=[3]
from 
(
    select 
        t.column1,
        split_values=SUBSTRING( t.column2, t1.N, ISNULL(NULLIF(CHARINDEX(',',t.column2,t1.N),0)-t1.N,8000)),
        r= row_number() over( partition by column1 order by t1.N) 
    from cte t 
        join
        (
            select 
                t.column2,
                1 as N 
            from cte t  
                UNION ALL
            select 
                t.column2,
                t1.N + 1 as N
            from cte t 
                join
                (
                 select 
                    top 8000
                        row_number() over(order by (select NULL)) as N 
                 from 
                    sys.objects s1 
                        cross join 
                   sys.objects s2 
                ) t1 
            on SUBSTRING(t.column2,t1.N,1) = ','
         ) t1
          on t1.column2=t.column2
)a
pivot
( 
    max(split_values) for r in ([1],[2],[3])
   )p

see working demo

Answer 3

;WITH Split_Names (data, xmlname)
AS
(
    SELECT data,

    CONVERT(XML,'<Names><name>'  
    + REPLACE(data,',', '</name><name>') + '</name></Names>') AS xmlname
      FROM TTT
)

SELECT  CASE
           WHEN s.post IS NULL
           THEN LEFT(s.last, CHARINDEX(' ', s.last)-1)
           ELSE s.last
       END last,
       CASE
           WHEN s.post IS NULL
           THEN SUBSTRING(s.last, (CHARINDEX(' ', s.last)+1), LEN(s.last))
           ELSE s.first
       END first,
       CASE
           WHEN s.post IS NULL
           THEN s.first
           ELSE s.post
       END Post FROM
(
SELECT data,      
 xmlname.value('/Names[1]/name[1]','varchar(MAX)') AS Last,    
 xmlname.value('/Names[1]/name[2]','varchar(MAX)') AS First,
 xmlname.value('/Names[1]/name[3]','varchar(MAX)') AS Post
 FROM Split_Names
)s