T-SQL substring - separating first and last name

问题:

I have a column which has FirstName and LastName together. I'm writing a report to separate the FirstName And LastName. How do I get the FirstName and LastName separated in T-SQL?

回答1:

Assuming the FirstName is all of the characters up to the first space:

SELECT
  SUBSTRING(username, 1, CHARINDEX(' ', username) - 1) AS FirstName,
  SUBSTRING(username, CHARINDEX(' ', username) + 1, 8000) AS LastName
FROM
  whereever

回答2:

The easiest way I can find to do it is:

SELECT 
  SUBSTRING(FullName, 1, CHARINDEX(' ', FullName) - 1) AS FirstName,
  REVERSE(SUBSTRING(REVERSE(FullName), 1, CHARINDEX(' ', REVERSE(FullName)) - 1)) AS LastName
FROM
  [PERSON_TABLE]

回答3:

This should work:

Select  
    LTRIM(RTRIM(SUBSTRING(FullName, 0, CHARINDEX(' ', FullName)))) As FirstName
,   LTRIM(RTRIM(SUBSTRING(FullName, CHARINDEX(' ', FullName)+1, 8000)))As LastName
FROM TABLE

Edit: Adopted Aaron's and Jonny's hint with the fixed length of 8000 to avoid unnecessary calculations.

回答4:

validate last name is blank

SELECT  
person.fullName,
(CASE WHEN 0 = CHARINDEX(' ', person.fullName) 
    then  person.fullName 
    ELSE SUBSTRING(person.fullName, 1, CHARINDEX(' ', person.fullName)) end) as first_name,  
(CASE WHEN 0 = CHARINDEX(' ', person.fullName) 
    THEN ''  
    ELSE SUBSTRING(person.fullName,CHARINDEX(' ', person.fullName), LEN(person.fullName) )end) last_name

FROM person

回答5:

This will take care of names like "Firstname Z. Lastname" and "First Z Last"

SELECT
CASE 
    WHEN CHARINDEX(' ',name) = 0 THEN name
    WHEN CHARINDEX(' ',name) = PATINDEX('% _[., ]%',name) THEN RTRIM(SUBSTRING(name, 1, CHARINDEX(' ',name) + 2)) 
    ELSE SUBSTRING(name,1, CHARINDEX(' ',name))
END [firstname]
,CASE 
    WHEN CHARINDEX(' ',name) = 0 THEN ''
    WHEN CHARINDEX(' ',name) = PATINDEX('% _[., ]%',name) THEN LTRIM(SUBSTRING(name, CHARINDEX(' ',name) + 3,1000)) 
    ELSE SUBSTRING(name,CHARINDEX(' ',name)+1,1000)
END [lastname]
FROM [myTable]

回答6:

Here is a more elaborated solution with a SQL function:

GetFirstname

CREATE FUNCTION [dbo].[ufn_GetFirstName]  
(  
 @FullName varchar(500)  
)  
RETURNS varchar(500)  
AS  
BEGIN  
 -- Declare the return variable here  
 DECLARE @RetName varchar(500)  

 SET @FullName = replace( replace( replace( replace( @FullName, '.', '' ), 'Mrs', '' ), 'Ms', '' ), 'Mr', '' )  

 SELECT   
  @RetName =   
    CASE WHEN charindex( ' ', ltrim( rtrim( @FullName ) ) ) > 0 THEN left( ltrim( rtrim( @FullName ) ), charindex( ' ', ltrim( rtrim( @FullName  ) ) ) - 1 ) ELSE '' END  

 RETURN @RetName  
END

GetLastName

CREATE FUNCTION [dbo].[ufn_GetLastName]  
(  
 @FullName varchar(500)  
)  
RETURNS varchar(500)  
AS  
BEGIN  
 DECLARE @RetName varchar(500)  

 IF(right(ltrim(rtrim(@FullName)), 2) <> ' I')  
 BEGIN  
  set @RetName = left(   
   CASE WHEN   
    charindex( ' ', reverse( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) ) ) > 0   
   THEN   
    right( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) , charindex( ' ', reverse( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) )  ) - 1 )   
   ELSE '' END  
  , 25 )  
 END  
 ELSE  
 BEGIN  
  SET @RetName = left(   
   CASE WHEN   
    charindex( ' ', reverse( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' I', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) ) ) > 0   
   THEN   
    right( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' I', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) , charindex( ' ', reverse( ltrim( rtrim(   
    replace( replace( replace( replace( replace( replace( replace( @FullName, ' Jr', '' ), ' III', '' ), ' II', '' ), ' I', '' ), ' Jr.', '' ), ' Sr', ''), 'Sr.', '')  
    ) ) )  ) - 1 )   
   ELSE '' END  
  , 25 )  
 END  

 RETURN @RetName  
END

USE:

SELECT dbo.ufn_GetFirstName(Fullname) as FirstName, dbo.ufn_GetLastName(Fullname) as LastName FROM #Names

回答7:

I think below query will be helpful to split FirstName and LastName from FullName even if there is only FirstName. For example: 'Philip John' can be split into Philip and John. But if there is only Philip, because of the charIndex of Space is 0, it will only give you ''.

Try the below one.

declare @FullName varchar(100)='Philp John'

Select  
    LTRIM(RTRIM(SUBSTRING(@FullName, 0, CHARINDEX(' ', @FullName+' ')))) As FirstName
,   LTRIM(RTRIM(SUBSTRING(@FullName, CHARINDEX(' ', @FullName+' ')+1, 8000)))As LastName

Hope this will help you. :)

回答8:

You could do this if firstname and surname are separated by space:

SELECT SUBSTRING(FirstAndSurnameCol, 0, CHARINDEX(' ', FirstAndSurnameCol)) Firstname,
SUBSTRING(FirstAndSurnameCol, CHARINDEX(' ', FirstAndSurnameCol)+1, LEN(FirstAndSurnameCol)) Surname FROM ...

回答9:

You may have problems if the Fullname doesn't contain a space. Assuming the whole of FullName goes to Surname if there is no space and FirstName becomes an empty string, then you can use this:

SELECT
  RTRIM(LEFT(FullName, CHARINDEX(' ', FullName))) AS FirstName,
  SUBSTRING(FullName, CHARINDEX(' ', FullName) + 1, 8000) AS LastName
FROM
  MyNameTable;

回答10:

The code below works with Last, First M name strings. Substitute "Name" with your name string column name. Since you have a period as a final character when there is a middle initial, you would replace the 2's with 3's in each of the lines (2, 6, and 8)- and change "RIGHT(Name, 1)" to "RIGHT(Name, 2)" in line 8.

SELECT  SUBSTRING(Name, 1, CHARINDEX(',', Name) - 1) LastName ,
CASE WHEN LEFT(RIGHT(Name, 2), 1) <> ' '
     THEN LTRIM(SUBSTRING(Name, CHARINDEX(',', Name) + 1, 99))
     ELSE LEFT(LTRIM(SUBSTRING(Name, CHARINDEX(',', Name) + 1, 99)),
               LEN(LTRIM(SUBSTRING(Name, CHARINDEX(',', Name) + 1, 99)))
               - 2)
END FirstName ,
CASE WHEN LEFT(RIGHT(Name, 2), 1) = ' ' THEN RIGHT(Name, 1)
     ELSE NULL
END MiddleName

回答11:

For the last name as in US standards (i.e., last word in the [Full Name] column) and considering first name to include a possible middle initial, middle name, etc.:

SELECT DISTINCT
             [Full Name]
            ,REVERSE([Full Name])                   --  to visualize what the formula is doing
            ,CHARINDEX(' ', REVERSE([Full Name]))   --  finds the last space in the string
            ,[Last Name]    =   REVERSE(RTRIM(LTRIM(LEFT(REVERSE([Full Name]), CHARINDEX(' ', REVERSE([Full Name]))))))
            ,[First Name]   =   RTRIM(LTRIM(LEFT([Full Name], LEN([Full Name]) - CHARINDEX(' ', REVERSE([Full Name])))))

FROM ...

Note that this assumes [Full Name] has no spaces before or after the actual string. Otherwise, use RTRIM and LTRIM to remove these.