aggregate multiple columns over dynamic pivot in sql - tsql

Question

I'm creating a stored procedure that would allow the user to retrieve data from 2 tables by providing the PersonID number as a parameter.
I thought of using the pivot function to pivot the Data table dynamically by non-aggregating over multiple columns and retrieving data from ONE column in a different table. The 2 tables below are just sample data as I have over 100 columns for the data table, hence the dynamic part. The 2 tables doesn't have a common ID column but just a common column_name.
Here are the 2 tables:
Mapping Table:
CREATE table #table (
ID varchar(10) NOT NULL,
Column_Name varchar (255) NOT NULL,
Page_Num varchar(10) NOT NULL,
Line_Num varchar(10) NOT NULL,
Element_Num varchar(10) NOT NULL
)
INSERT INTO #table (ID,Column_Name,Page_Num,Line_Num,Element_Num) VALUES ('1','Name', 'DT-01', '200','20')
INSERT INTO #table (ID,Column_Name,Page_Num,Line_Num,Element_Num) VALUES ('2','SSN', 'DT-02', '220','10')
INSERT INTO #table (ID,Column_Name,Page_Num,Line_Num,Element_Num) VALUES ('3','City', 'DT-03', '300','11')
INSERT INTO #table (ID,Column_Name,Page_Num,Line_Num,Element_Num) VALUES ('4','StreetName', 'DT-04', '350','33')
INSERT INTO #table (ID,Column_Name,Page_Num,Line_Num,Element_Num) VALUES ('5','Sex', 'DT-05', '310','51')
Creates:
ID Column_Name Page_Num Line_Num Element_Num
_________________________________________________________________
1 Name DT-01 200 20
2 SSN DT-02 220 10
3 City DT-03 300 11
4 StreetName DT-04 350 33
5 Sex DT-05 310 51
Data table:
CREATE table #temp (
PersonID varchar (100) NOT NULL,
Name varchar(100) NOT NULL,
SSN varchar (255) NOT NULL,
City varchar(100) NOT NULL,
StreetName varchar(100) NOT NULL,
Sex varchar(100) NOT NULL
)
INSERT INTO #temp (PersonID,Name,SSN,City,StreetName,Sex) VALUES ('112','Joe','945890189', 'Lookesville', 'Broad st','Male')
INSERT INTO #temp (PersonID,Name,SSN,City,StreetName,Sex) VALUES ('140','Santana','514819926', 'Falls Church', 'Gane Rd', 'Female')
INSERT INTO #temp (PersonID,Name,SSN,City,StreetName,Sex) VALUES ('481','Wyatt','014523548','Gainesville', 'Westfield blvd', 'Male')
INSERT INTO #temp (PersonID,Name,SSN,City,StreetName,Sex) VALUES ('724','Brittany','551489230','Aldi', 'Ostrich rd', 'Female')
INSERT INTO #temp (PersonID,Name,SSN,City,StreetName,Sex) VALUES ('100','Giovanni','774451362','Paige', 'Company ln', 'Male')
Creates:
PersonID Name SSN City StreetName Sex
_______________________________________________________________________
112 Joe 945890189 Lookesville Broad st Male
140 Santana 514819926 Falls Church Gane Rd Female
481 Wyatt 014523548 Gainesville Westfield rd Male
724 Brittany 551489230 Aldi Ostrich rd Female
100 Giovanni 774451362 Paige Company ln Male
The end result should be:
Example: User enters parameter PersonID = 140
Column_name Page_Num Line_Num Element_Num Data
_____________________________________________________________________________
Name DT-01 200 20 Santana
SSN DT-02 220 10 514819926
City DT-03 300 11 Falls Church
StreetName DT-04 350 33 Gane Rd
Sex DT-05 310 51 Female
... ... ... ... ...
and so on..

Answer 1

The following will dynamically unpivot a data row, and then perform a join on the field name with the def data.
If you want to run this query without a filter, I would suggest adding A.PersonID to the top SELECT and remove the WHERE
I should add, UNPIVOT would be more performant, but with this approach, there is no need to define and/or recast values. That said, the performance is still very respectable.
Example
Select D.*
,Data=C.Value
From #Temp A
Cross Apply (Select XMLData = cast((Select A.* For XML Raw) as xml)) B
Cross Apply (
Select Item = attr.value('local-name(.)','varchar(100)')
,Value = attr.value('.','varchar(max)')
From B.XMLData.nodes('/row') as X(r)
Cross Apply X.r.nodes('./#*') AS N(attr)
) C
Join #Table D on (C.Item=D.Column_Name)
Where PersonID=140
Returns
If it Helps with the Visualization, the CROSS APPLY C generates the following:
EDIT - As a Stored Procedure
CREATE PROCEDURE [dbo].[YourProcedureName](#PersonID int)
As
Begin
Set NoCount On;
Select D.*
,Data=C.Value
From YourPersonTableName A
Cross Apply (Select XMLData = cast((Select A.* For XML Raw) as xml)) B
Cross Apply (
Select Item = attr.value('local-name(.)','varchar(100)')
,Value = attr.value('.','varchar(max)')
From B.XMLData.nodes('/row') as X(r)
Cross Apply X.r.nodes('./#*') AS N(attr)
) C
Join YourObjectTableName D on (C.Item=D.Column_Name)
Where PersonID=#PersonID
End