Insert XML data into multiple tables in SQL Server - sql-server

Question

I have a XML like below :
<Employees>
<Employee>
<AccountInfo>
<AccountNumber>1234567</AccountNumber>
<AccountType>Test</AccountType>
</AccountInfo>
<DocumentType>Test Doc</DocumentType>
<Date>12/01/2020</Date>
<Description>Test Description</Description>
<ImageFileType>pdf</ImageFileType>
<ImageFileName>321.PDF</ImageFileName>
<AdditionalInfo>
<FieldName>docDescription</FieldName>
<FieldValue>ABC XYZ</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>Creation Date</FieldName>
<FieldValue>12/01/2020</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>Department Code</FieldName>
<FieldValue>63</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>ID No</FieldName>
<FieldValue>3214567</FieldValue>
</AdditionalInfo>
</Employee>
</Employees>
I want to insert this XML data into 3 tables EmployeeInfo, AccountInfo and AdditionalInfo with schema like this:
EmployeeInfo
(
EmployeeNumber Int Identity(1,1) NOT NULL,
DocumentType varchar(500) NULL,
[Description] varchar(500) NULL,
ImageFileName varchar(500) NULL,
ImageFileType varchar(500) NULL,
[Date] varchar(500) NULL
);
AccountInfo
(
EmployeeNumber int NOT NULL,
AccountNumber varchar(500) NULL,
AccountType varchar(500) NULL
);
AdditionalInfo
(
EmployeeNumber int NOT NULL,
FieldName varchar(500) NULL,
FieldValue varchar(500) NULL
);
EmployeeNumber column is used for linking AccountInfo and AdditionalInfo table with EmployeeInfo.
AccountInfo table will get below node:
<AccountInfo>
<AccountNumber>1234567</AccountNumber>
<AccountType>Test</AccountType>
</AccountInfo>
The AdditionalInfo table will get these XML nodes:
<AdditionalInfo>
<FieldName>docDescription</FieldName>
<FieldValue>ABC XYZ</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>Creation Date</FieldName>
<FieldValue>12/01/2020</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>Department Code</FieldName>
<FieldValue>63</FieldValue>
</AdditionalInfo>
<AdditionalInfo>
<FieldName>ID No</FieldName>
<FieldValue>3214567</FieldValue>
</AdditionalInfo>
Rest xml node are inserted into EmployeeInfo.
I tried with the query shown here. I'm able to get xml data and insert it into main table EmployeeInfo, but not able to link AdditionalInfo and AccountInfo with identity generated in EmployeeInfo table.
Note: I have multiple employee nodes in the xml.
DECLARE #EmpNumber int
DECLARE #x xml
SELECT #x = X FROM OPENROWSET (BULK 'C:\Test\Sample.xml', SINGLE_BLOB) AS EmpInfo(X)
DECLARE #hdoc int
EXEC sp_xml_preparedocument #hdoc OUTPUT, #x
INSERT INTO EmployeeInfo (DocumentType, [Description], ImageFileName, ImageFileType, [Date])
SELECT * FROM OPENXML (#hdoc, '/Employees/Employee', 2)
WITH ( DocumentType varchar(500), [Description] varchar(500), ImageFileName varchar(500), ImageFileType varchar(500), [Date] varchar(500))
SELECT #EmpNumber=SCOPE_IDENTITY()
INSERT INTO AccountInfo ([EmployeeNumber],[AccountNumber], [AccountType])
SELECT #EmpNumber, *
FROM OPENXML (#hdoc, '/Employees/Employee/AccountInfo', 2)
WITH (AccountNumber varchar(500), AccountType varchar(500))
INSERT INTO AdditionalInfo ([EmployeeNumber],[FieldName], [FieldValue])
SELECT #EmpNumber, *
FROM OPENXML (#hdoc, '/Employees/Employee/AdditionalInfo', 2)
WITH (
FieldName varchar(5000), FieldValue varchar(5000)
)
EXEC sp_xml_removedocument #hdoc
Can someone help me out in this. Thanks in Advance.

Answer 1

Here is a conceptual example how to do it.
Two tables, state as a parent, and city as a child, with one-to-many relationship. Primary keys are IDENTITY based.
INSERT into a parent table generates new IDENTITY values that are captured and stored in a table variable, and later used to INSERT into a child table to preserve foreign key constraint.
SQL
-- DDL and sample data population, start
USE tempdb;
GO
DROP TABLE IF EXISTS #city;
DROP TABLE IF EXISTS #state;
-- parent table
CREATE TABLE #state (
stateID INT IDENTITY PRIMARY KEY,
stateName VARCHAR(30),
abbr CHAR(2),
capital VARCHAR(30)
);
-- child table (1-to-many)
CREATE TABLE #city (
cityID INT IDENTITY,
stateID INT NOT NULL FOREIGN KEY REFERENCES #state(stateID),
city VARCHAR(30),
[population] INT,
PRIMARY KEY (cityID, stateID, city)
);
-- mapping table to preserve IDENTITY ids
DECLARE #idmapping TABLE (GeneratedID INT PRIMARY KEY,
NaturalID VARCHAR(20) NOT NULL UNIQUE);
DECLARE #xml XML =
N'<root>
<state>
<StateName>Florida</StateName>
<Abbr>FL</Abbr>
<Capital>Tallahassee</Capital>
<cities>
<city>
<city>Miami</city>
<population>470194</population>
</city>
<city>
<city>Orlando</city>
<population>285713</population>
</city>
</cities>
</state>
<state>
<StateName>Texas</StateName>
<Abbr>TX</Abbr>
<Capital>Austin</Capital>
<cities>
<city>
<city>Houston</city>
<population>2100263</population>
</city>
<city>
<city>Dallas</city>
<population>5560892</population>
</city>
</cities>
</state>
</root>';
-- DDL and sample data population, end
;WITH rs AS
(
SELECT stateName = p.value('(StateName/text())[1]', 'VARCHAR(30)'),
abbr = p.value('(Abbr/text())[1]', 'CHAR(2)'),
capital = p.value('(Capital/text())[1]', 'VARCHAR(30)')
FROM #xml.nodes('/root/state') AS t(p)
)
MERGE #state AS o
USING rs ON 1 = 0
WHEN NOT MATCHED THEN
INSERT(stateName, abbr, capital)
VALUES(rs.stateName, rs.Abbr, rs.Capital)
OUTPUT inserted.stateID, rs.stateName
INTO #idmapping (GeneratedID, NaturalID);
;WITH Details AS
(
SELECT NaturalID = p.value('(StateName/text())[1]', 'VARCHAR(30)'),
city = c.value('(city/text())[1]', 'VARCHAR(30)'),
[population] = c.value('(population/text())[1]', 'INT')
FROM #xml.nodes('/root/state') AS A(p) -- parent
CROSS APPLY A.p.nodes('cities/city') AS B(c) -- child
)
INSERT #city (stateID, city, [Population])
SELECT m.GeneratedID, d.city, d.[Population]
FROM Details AS d
INNER JOIN #idmapping AS m ON d.NaturalID = m.NaturalID;
-- test
SELECT * FROM #state;
SELECT * FROM #idmapping;
SELECT * FROM #city;

Answer 2

Avoid using sp_xml_preparedocument, OPENXML and sp_xml_removedocument because they are inefficient, often cause resource leakage when sp_xml_removedocument is forgotten, and encourage RBAR-like constructs in what's supposed to be a set-based RDBMS.
Prefer to use nodes() and value() where possible, such as with the following...
insert dbo.EmployeeInfo (DocumentType, [Description], ImageFileName, ImageFileType, [Date])
select
Employee.value('(DocumentType/text())[1]', 'varchar(500)'),
Employee.value('(Description/text())[1]', 'varchar(500)'),
Employee.value('(ImageFileName/text())[1]', 'varchar(500)'),
Employee.value('(ImageFileType/text())[1]', 'varchar(500)'),
Employee.value('(Date/text())[1]', 'varchar(500)')
from #xml.nodes('/Employees/Employee') root(Employee);
declare #EmpNumber int = SCOPE_IDENTITY();
insert dbo.AccountInfo ([EmployeeNumber], [AccountNumber], [AccountType])
select
#EmpNumber,
AccountInfo.value('(AccountNumber/text())[1]', 'varchar(500)'),
AccountInfo.value('(AccountType/text())[1]', 'varchar(500)')
from #xml.nodes('/Employees/Employee/AccountInfo') root(AccountInfo);
insert dbo.AdditionalInfo ([EmployeeNumber], [FieldName], [FieldValue])
select
#EmpNumber,
AdditionalInfo.value('(FieldName/text())[1]', 'varchar(500)'),
AdditionalInfo.value('(FieldValue/text())[1]', 'varchar(500)')
from #xml.nodes('/Employees/Employee/AdditionalInfo') root(AdditionalInfo);