Creating an Alphabetical Indexed List (ColdFusion + Microsoft SQL Server)

问题

I'm currently struggling to find anyone who knows how this can be done? I've tried a few different methods and ended up with halfway results but not quite what i wanted. Basically i'm trying to create a list showing all the bands A-Z, but the band names are being called from a database, so i'm having to use #band_name# within a nested list. If i re-write the code and post it, someone might be able to see where i'm going wrong.

<cfoutput query="bandNameList">
  <cfloop from="65" to="90" index="i">
    <UL>
     <LI> #chr(i)#
       <UL>
         <LI> #band_name# </LI>
       </UL>
     </LI>
    </UL>
  </cfloop>
</cfoutput>

回答1:

What I think you're after is to only output the Letter for the first band that begins with that letter. One way to achieve this is to change your query slightly (note I'm using what I think is SQL-92 syntax here, but there's probably a nicer way to get the first letter in your particular database):

select 
  band_name, 
  SUBSTRING(band_name from 1 for 1) AS first_letter
from 
  bands 
order by 
  band_name

Which will get you the first letter in the query.

If you want to group all the bands with numeric first letters together, then you can use SQL's CASE statement to do that (you may need to find the equivalent to ascii() in your DBMS). You could also invert the logic and match against 'normal' letters and lump everything else into a '0-9 and punctuation' category if that's easier. I think that's what a number of music systems do (I'm thinking iTunes on the iPhone, but I'm sure there are others)

select 
  band_name, 
  CASE  
    WHEN ascii(left(band_name, 1)) BETWEEN 48 AND 57 THEN '0-9'
    ELSE left(band_name, 1)
  END AS first_letter   
from 
  bands 
order by 
  band_name

Now you can use that extra column along with cfoutput's group attribute to help get the output as you want it.

<UL>
<cfoutput query="bandNameList" group="first_letter">
     <LI> #first_letter#
     <UL>
       <cfoutput>             
           <LI> #band_name# </LI>             
       </cfoutput>
       </UL>
     </LI>        
</cfoutput>
</UL>

回答2:

Update your query to have a left(band_name,1) AS BandStart and make sure to order by band_name in your ORDER BY. Then use group to output the list.

<cfoutput query="bandNameList" group="BandStart">
 <UL>
  <LI>#bandNameList.BandStart#
   <cfoutput>
    <UL>
     <LI> #bandNameList.band_name# </LI>
    </UL>
   </cfoutput>
  </LI>
 </UL>
</cfoutput>

回答3:

If you want to display all letters, even if no bands starting with that letter exist, another option is using a CTE to generate a table of letters A-Z. Then display the results with a "grouped" cfoutput:

<cfquery name="getBandNameList" ...>
    ;WITH ltrs ( code ) AS (
        SELECT  ascii('A') AS code 
        UNION ALL           
        SELECT  code + 1
        FROM    ltrs
        WHERE   ascii('Z') > code
    )
    SELECT char(code) AS letter, t.band_name
    FROM   ltrs LEFT JOIN @YourTable t ON t.band_name LIKE char(code) +'%'
    ORDER BY letter ASC, t.band_name ASC
</cfquery>

<cfoutput query="bandNameList" group="Letter">
    <UL>
     <LI> #letter#
       <UL>
         <cfoutput>
            <LI> #band_name# </LI>
         </cfoutput>
       </UL>
     </LI>
    </UL>
</cfoutput>

回答4:

Another approach is to write a sql server stored proc that returns everything in a single query object. The code would resemble this:

declare @thisNum as int
declare @lastNum as int
set @thisNum = 65;
set @lastNum = 90;

declare @letters as table(letter char(1))

while (@thisNum <= @lastNum)
begin
insert into @letters values (CHAR(@thisNum))
set @thisNum = @thisNum + 1;
end

select letter, bandname
from @letters left join band on letter = left(bandname, 1)
order by letter, bandname

Then, in ColdFusion, you can use cfoutput with the group attribute.

回答5:

Try this code ::

<cfquery datasource="orcl" name="list">
select upper(brand) brand from tbl
</cfquery>
<cfoutput query="list">
  <cfloop from="65" to="90" index="i">
    <UL>
     <LI> #chr(i)#
       <UL>
         <LI><cfif mid(brand,1,1) eq chr(i)> #brand#</cfif></LI>
       </UL>
     </LI>
    </UL>
  </cfloop>
</cfoutput>

来源：https://stackoverflow.com/questions/13728189/creating-an-alphabetical-indexed-list-coldfusion-microsoft-sql-server

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coldfusion