[sql] How to split a single column values to multiple column values?

I have a problem splitting single column values to multiple column values.

For Example:

Name
------------
abcd efgh
ijk lmn opq
asd j. asdjja
asb (asdfas) asd
asd

and I need the output something like this:

first_name             last_name
----------------------------------
abcd                     efgh
ijk                      opq
asd                      asdjja
asb                      asd
asd                      null

The middle name can be omitted (no need for a middle name) The columns are already created and need to insert the data from that single Name column.

I used it recently:

select 
substring(name,1,charindex(' ',name)-1) as Col1,
substring(name,charindex(' ',name)+1,len(name)) as Col2 
from TableName

An alternative to Martin's

select LEFT(name, CHARINDEX(' ', name + ' ') -1),
       STUFF(name, 1, Len(Name) +1- CHARINDEX(' ',Reverse(name)), '')
from somenames

Sample table

create table somenames (Name varchar(100))
insert somenames select 'abcd efgh'
insert somenames select 'ijk lmn opq'
insert somenames select 'asd j. asdjja'
insert somenames select 'asb (asdfas) asd'
insert somenames select 'asd'
insert somenames select ''
insert somenames select null

What you need is a split user-defined function. With that, the solution looks like

With SplitValues As
    (
    Select T.Name, Z.Position, Z.Value
        , Row_Number() Over ( Partition By T.Name Order By Z.Position ) As Num
    From Table As T
        Cross Apply dbo.udf_Split( T.Name, ' ' ) As Z
    )
Select Name
    , FirstName.Value
    , Case When ThirdName Is Null Then SecondName Else ThirdName End As LastName
From SplitValues As FirstName
    Left Join SplitValues As SecondName
        On S2.Name = S1.Name
            And S2.Num = 2
    Left Join SplitValues As ThirdName
        On S2.Name = S1.Name
            And S2.Num = 3
Where FirstName.Num = 1

Here's a sample split function:

Create Function [dbo].[udf_Split]
(   
    @DelimitedList nvarchar(max)
    , @Delimiter nvarchar(2) = ','
)
RETURNS TABLE 
AS
RETURN 
    (
    With CorrectedList As
        (
        Select Case When Left(@DelimitedList, Len(@Delimiter)) <> @Delimiter Then @Delimiter Else '' End
            + @DelimitedList
            + Case When Right(@DelimitedList, Len(@Delimiter)) <> @Delimiter Then @Delimiter Else '' End
            As List
            , Len(@Delimiter) As DelimiterLen
        )
        , Numbers As 
        (
        Select TOP( Coalesce(DataLength(@DelimitedList)/2,0) ) Row_Number() Over ( Order By c1.object_id ) As Value
        From sys.columns As c1
            Cross Join sys.columns As c2
        )
    Select CharIndex(@Delimiter, CL.list, N.Value) + CL.DelimiterLen As Position
        , Substring (
                    CL.List
                    , CharIndex(@Delimiter, CL.list, N.Value) + CL.DelimiterLen     
                    , CharIndex(@Delimiter, CL.list, N.Value + 1)                           
                        - ( CharIndex(@Delimiter, CL.list, N.Value) + CL.DelimiterLen ) 
                    ) As Value
    From CorrectedList As CL
        Cross Join Numbers As N
    Where N.Value <= DataLength(CL.List) / 2
        And Substring(CL.List, N.Value, CL.DelimiterLen) = @Delimiter
    )

SELECT
   SUBSTRING_INDEX(SUBSTRING_INDEX(rent, ' ', 1), ' ', -1) AS currency,
   SUBSTRING_INDEX(SUBSTRING_INDEX(rent, ' ', 3), ' ', -1) AS rent
FROM tolets

;WITH Split_Names (Name, xmlname)
AS
(
    SELECT 
    Name,
    CONVERT(XML,'<Names><name>'  
    + REPLACE(Name,' ', '</name><name>') + '</name></Names>') AS xmlname
      FROM somenames
)

 SELECT       
 xmlname.value('/Names[1]/name[1]','varchar(100)') AS first_name,    
 xmlname.value('/Names[1]/name[2]','varchar(100)') AS last_name
 FROM Split_Names

and also check the link below for reference

http://jahaines.blogspot.in/2009/06/converting-delimited-string-of-values.html

Here is how I did this on a SQLite database:

SELECT SUBSTR(name, 1,INSTR(name, " ")-1) as Firstname,
SUBSTR(name, INSTR(name," ")+1, LENGTH(name)) as Lastname
FROM YourTable;

Hope it helps.