Day #3 with SQL Server.
I am trying to combine 2 columns of delimited data into one output from a Table Valued Function. Here is my data:
I would like the data to be processed and placed into a table in the following format:
I am currently trying to use this CROSS APPLY TSQL statement, but I don't know what I'm doing.
USE [Metrics]
INSERT INTO dbo.tblSplitData(SplitKey, SplitString, SplitValues)
SELECT d.RawKey, c.*, e.*
FROM dbo.tblRawData d
CROSS APPLY dbo.splitstringcomma(d.DelimitedString) c, dbo.splitstringcomma(d.DelimitedValues) e
My research on CROSS APPLY has broad context, and I don't understand how it should be applied in this scenario. Do I need a subquery with an additional CROSS APPLY and a join to combine the returns from the two Table Valued Functions?
Here is the split function I was using originally (I can't remember the author to credit them):
CREATE FUNCTION [dbo].[splitstring] ( @stringToSplit VARCHAR(MAX), @Delimiter CHAR(1))
RETURNS
@returnList TABLE ([Name] [nvarchar] (500))
AS
BEGIN
DECLARE @name NVARCHAR(255)
DECLARE @pos INT
WHILE CHARINDEX(@Delimiter, @stringToSplit) > 0
BEGIN
SELECT @pos = CHARINDEX(@Delimiter, @stringToSplit)
SELECT @name = SUBSTRING(@stringToSplit, 1, @pos-1)
INSERT INTO @returnList
SELECT @name
SELECT @stringToSplit = SUBSTRING(@stringToSplit, @pos+1, LEN(@stringToSplit)-@pos)
END
INSERT INTO @returnList
SELECT @stringToSplit
RETURN
END
Edit & Revised Query
USE [Metrics]
INSERT INTO dbo.tblSplitData(SplitKey, SplitString, SplitValues)
SELECT s.RawKey, s.SplitString, v.SplitValues
FROM (
SELECT d.RawKey, d.DelimitedString,
c.item SplitString, c.rn
FROM dbo.tblRawData d
CROSS APPLY dbo.splitstring(d.DelimitedString, ',') c
) s
INNER JOIN
(
SELECT d.RawKey, d.DelimitedValues,
c.item SplitValues, c.rn
FROM dbo.tblRawData d
CROSS APPLY dbo.splitstring(d.DelimitedValues, ',') c
) v
on s.RawKey = v.RawKey
and s.rn = v.rn;
It might be easier to answer this if we could see your split string function. My answer is using a version of my split function that I have.
I would include in your split function a row number that you can use to JOIN the split string and the split values.
Split function:
CREATE FUNCTION [dbo].[Split](@String varchar(MAX), @Delimiter char(1))
returns @temptable TABLE (items varchar(MAX), rn int)
as
begin
declare @idx int
declare @slice varchar(8000)
declare @rn int = 1 -- row number that increments with each value in the delimited string
select @idx = 1
if len(@String)<1 or @String is null return
while @idx!= 0
begin
set @idx = charindex(@Delimiter,@String)
if @idx!=0
set @slice = left(@String,@idx - 1)
else
set @slice = @String
if(len(@slice)>0)
insert into @temptable(Items, rn) values(@slice, @rn)
set @String = right(@String,len(@String) - @idx)
set @rn = @rn +1
if len(@String) = 0 break
end
return
end;
Then if you have multiple columns to split, you could use a query similar to the following:
INSERT INTO dbo.tblSplitData(SplitKey, SplitString, SplitValues)
select s.rawkey,
s.splitstring,
v.splitvalues
from
(
SELECT d.RawKey, d.delimitedstring, d.delimitedvalues,
c.items SplitString,
c.rn
FROM dbo.tblRawData d
CROSS APPLY dbo.Split(d.DelimitedString, ',') c
) s
inner join
(
SELECT d.RawKey, d.delimitedstring, d.delimitedvalues,
c.items SplitValues,
c.rn
FROM dbo.tblRawData d
CROSS APPLY dbo.Split(d.DelimitedValues, ',') c
) v
on s.rawkey = v.rawkey
and s.delimitedstring = v.delimitedstring
and s.rn = v.rn;
This uses two subqueries that generate the list of split values, then they are joined using the row number created by the split function.