查找大寫字母，然後添加空間

Question

我買了一個SQL世界城市/州數據庫。在狀態數據庫中，它的狀態名稱拼合在一起。示例：「NorthCarolina」或「SouthCarolina」...

是否有一種方法在SQL中循環並查找大寫字符並添加空格？

這樣「NorthCarolina」變成「北卡羅萊納州」？

Answer 1

有幾個方法可以解決這個

1. 構造使用模式和PATINDEX feature功能。

2. 鏈最小REPLACE語句每種情況下（如REPLACE(state_name, 'hC', 'h C' for your example case)，這似乎是一種黑客攻擊，但實際上可能給你最好的性能，因爲你有這樣一個小套更換的。

Answer 2

創建此功能

if object_id('dbo.SpaceBeforeCaps') is not null 
    drop function dbo.SpaceBeforeCaps 
GO 
create function dbo.SpaceBeforeCaps(@s varchar(100)) returns varchar(100) 
as 
begin 
    declare @return varchar(100); 
    set @return = left(@s,1); 
    declare @i int; 
    set @i = 2; 
    while @i <= len(@s) 
    begin 
     if ASCII(substring(@s,@i,1)) between ASCII('A') and ASCII('Z') 
      set @return = @return + ' ' + substring(@s,@i,1) 
     else 
      set @return = @return + substring(@s,@i,1) 
     set @i = @i + 1; 
    end; 
    return @return; 
end; 
GO 

然後你可以用它來更新數據庫

update tbl set statename = select dbo.SpaceBeforeCaps(statename); 

Answer 3

如果你絕對是不能創建函數並需要這個作爲一次性，你可以使用遞歸CTE來打斷字符串（並在需要的地方同時添加空間），然後使用FOR重新組合字符XML。下面是精心設計的例子：

-- some sample data 
create table #tmp (id int identity primary key, statename varchar(100)); 
insert #tmp select 'NorthCarolina'; 
insert #tmp select 'SouthCarolina'; 
insert #tmp select 'NewSouthWales'; 

-- the complex query updating the "statename" column in the "#tmp" table 
;with cte(id,seq,char,rest) as (
    select id,1,cast(left(statename,1) as varchar(2)), stuff(statename,1,1,'') 
     from #tmp 
    union all 
    select id,seq+1,case when ascii(left(rest,1)) between ascii('A') and ascii('Z') 
         then ' ' else '' end + left(rest,1) 
     , stuff(rest,1,1,'') 
     from cte 
    where rest > '' 
), recombined as (
    select a.id, (select b.char+'' 
        from cte b 
       where a.id = b.id 
       order by b.seq 
        for xml path, type).value('/','varchar(100)') fixed 
    from cte a 
group by a.id 
) 
update t 
    set statename = c.fixed 
    from #tmp t 
    join recombined c on c.id = t.id 
where statename != c.fixed; 

-- check the result 
select * from #tmp 

----------- ----------- 
id   statename 
----------- ----------- 
1   North Carolina 
2   South Carolina 
3   New South Wales