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Question

1. The MEMBERS table has the phone number broken into three fields:
   CountryCode - e,g., '1' for the United States
   AreaCode - e.g., three digits for the United States
   Phone - e.g., 7 digits, with or without a dash between the first three digits (Exchange) and last four digits (Line)
   Any or all of the fields may be missing (null) or blank or contain only spaces.
   Write a T-SQL statement to concatenate the three fields into a complete phone number
   with the format: CountryCode(AreaCode)Exchange-Line, e.g., 1(816)123-4567
   If no Phone is present, return a blank string.
   If no area code is present, return only the Phone number. Do not return an empty pair of parentheses or the CountryCode.
2. The PERSON_CAMPAIGN table contains a row for each war/conflict the member served in. A member may have served in multiple conflicts
   For this purpose, each row contains:
   PersonID - unique member identifier
   Campaign - name of war/conflict
   Write a T-SQL statement to return one row per member with all campaigns concatenated into a single field and separated by commas
   E.g., PersonID    Campaigns
         12345678    Global War on Terror, Iraq, Afghanistan
3. The MEMBER_STATISTICS table contains one row per post.
   For this purpose, each row contains the post's:
   Division - a way of grouping posts by their member size
   Department - the state in which the post is located
   PostNumber - unique post identifier
   Reinstated - count of members whose annual subscription had lapsed for at least two years but who have now subscribed for the current year
   Write a T-SQL statement to determine the top ten posts in each division based on the number of reinstated members, with a minimum of 50 reinstated members.
   Rank them by highest to lowest reinstated count.
   Return their Division, Rank, Department, PostNumber, Reinstated

Answer 1

I got 3 home work questions think i have the first two need help with the last one please.
Kinda stuck on #3 hard I can see data not sure witch to sum or count?
1. The MEMBERS table has the phone number broken into three fields:
   CountryCode - e,g., '1' for the United States
   AreaCode - e.g., three digits for the United States
   Phone - e.g., 7 digits, with or without a dash between the first three digits (Exchange) and last four digits (Line)
   Any or all of the fields may be missing (null) or blank or contain only spaces.
   Write a T-SQL statement to concatenate the three fields into a complete phone number
   with the format: CountryCode(AreaCode)Exchange-Line, e.g., 1(816)123-4567
   If no Phone is present, return a blank string.
   If no area code is present, return only the Phone number. Do not return an empty pair of parentheses or the CountryCode.
ANSWER******************
Notes: created a funtion to format the phone 
Then used the this function in a select to concatenate Phone 
 CREATE FUNCTION dbo.FORMATPHONE (@CountryCode int, @AreCode int, @Phone VARCHAR(14))
RETURNS VARCHAR(14)
    AS BEGIN
       DECLARE @ReturnPhone VARCHAR(14)
       DECLARE @NewPhone VARCHAR(14)
-- Note case sets newphone to null if phone null or '' also to see if phone has '-' in it if not inserts into newphone
       case 
            when @Phone is null or @Phone  = ''
               Then SET @NewPhone = Null
            when @Phone = substring(@Phone,4,1)='-'
      Then SET @NewPhone = @Phone 
       else  
            SET @NewPhone = substring(@Phone,1,3)+'-'+ substring(@Phone,4,4)
       End     
       case 
            when @NewPhone is null then SET @ReturnPhone = @NewPhone            
       elese case
                when @AreCode is null or @AreCode = '' then SET @ReturnPhone = @NewPhone
             else 
      SET @ReturnPhone = @CountryCode + '(' + @AreCode + ')' +  @NewPhone
            END
       END
    RETURN @ReturnPhone 
END
select dbo.FORMATPHONE(CountryCode,AreCode,Phone)
from MEMBERS 
2. The PERSON_CAMPAIGN table contains a row for each war/conflict the member served in. A member may have served in multiple conflicts
   For this purpose, each row contains:
   PersonID - unique member identifier
   Campaign - name of war/conflict
   Write a T-SQL statement to return one row per member with all campaigns concatenated into a single field and separated by commas
   E.g., PersonID    Campaigns
         12345678    Global War on Terror, Iraq, Afghanistan
ANSWER******************
SELECT      PersonID,
            STUFF((    SELECT ',' + Campaign AS [text()]
                        FROM PERSON_CAMPAIGN 
                        WHERE (PersonID = Results.ID)
                        FOR XML PATH('') 
                        ), 1, 1, '' )
            AS Campaigns
FROM  PERSON_CAMPAIGN Results
3. The MEMBER_STATISTICS table contains one row per post.
   For this purpose, each row contains the post's:
   Division - a way of grouping posts by their member size
   Department - the state in which the post is located
   PostNumber - unique post identifier
   Reinstated - count of members whose annual subscription had lapsed for at least two years but who have now subscribed for the current year
   Write a T-SQL statement to determine the top ten posts in each division based on the number of reinstated members, with a minimum of 50 reinstated members.
   Rank them by highest to lowest reinstated count.
   Return their Division, Rank, Department, PostNumber, Reinstated