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Bulk insert nested xml with foreign key as identity column of first table

I have xml like this:

<Records>
  <Record>
    <Name>Best of Pop</Name>
    <Studio>ABC studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>John</ArtistName>
        <Age>36</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Jessica</ArtistName>
        <Age>20</Age>            
      </Artist>
    </Artists>
  </Record>
  <Record>
    <Name>Nursery rhymes</Name>
    <Studio>XYZ studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>Judy</ArtistName>
        <Age>10</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Rachel</ArtistName>
        <Age>15</Age>            
      </Artist>
    </Artists>
  </Record>
</Records>

This file can contain millions of entries. My MS SQL database running on Azure SQL Database contains the following two tables to store these records:

  • Record

    (RecordId [PK, id, autoincrement], name, studio)

  • Artist

    (RecordId [Foreign Key refers to Record.RecordId], ArtistName, Age)

Is it possible Record

to bulk up the inserts of records into a table , get the RecordIds and then concatenate the inserts of artist information into the table Artist

in a single xml traversal using the xml nodes approach?

I've been looking for an efficient way to do this for a long time, but in vain.

I have tried approaches similar to those described here and here , but I can't seem to get to a solution.

Any pointers in the direction of a solution would be very helpful.

Update : @srutzky: Thanks for the solution. This works exactly as I wanted. But there is one catch. I have to use the nodes approach to solve. I changed the first part of the query. But I'm stuck in the second half. This is where I came to.

DECLARE @Record TABLE (RecordId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       Name NVARCHAR(400) UNIQUE,
                       Studio NVARCHAR(400));
DECLARE @Artist TABLE (ArtistId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       RecordId INT NOT NULL,
                       ArtistName NVARCHAR(400), Age INT);

INSERT INTO @Record (Name, Studio)
   SELECT  T.c.value(N'(Name/text())[1]', 'NVARCHAR(400)'),
           T.c.value(N'(Studio/text())[1]', 'NVARCHAR(400)')
 FROM @ImportData.nodes('/Records/Record') T(c);

SELECT * FROM @Record

Can you help me with the second part? I am new to this approach to XML processing.

UPDATE2 : And I did it ... I racked my brains for a couple of hours, tried a few things and finally came to a solution.

DECLARE @Record TABLE (RecordId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       Name NVARCHAR(400) UNIQUE,
                       Studio NVARCHAR(400));
DECLARE @Artist TABLE (ArtistId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       RecordId INT NOT NULL,
                       ArtistName NVARCHAR(400), 
                       Age INT);

INSERT INTO @Record (Name, Studio)
   SELECT  T.c.value(N'(Name/text())[1]', 'NVARCHAR(400)'),
           T.c.value(N'(Studio/text())[1]', 'NVARCHAR(400)')
 FROM @ImportData.nodes('/Records/Record') T(c);

INSERT INTO @Artist (RecordId, ArtistName, Age)
    SELECT  (SELECT RecordId FROM @Record WHERE Name=T.c.value(N'(../../Name/text())[1]', 'NVARCHAR(400)')),
            T.c.value(N'(ArtistName/text())[1]', 'NVARCHAR(400)'),
           T.c.value(N'(Age/text())[1]', 'INT')
 FROM @ImportData.nodes('/Records/Record/Artists/Artist') T(c);

 SELECT * FROM @Record
 SELECT * FROM @Artist

@srutzky: Thanks for pointing me in the right direction. Any suggestions for improving this solution are greatly appreciated.

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1 answer


This cannot be done in a single pass anyway, since you cannot insert two tables in the same DML statement (well, outside of triggers and the OUTPUT clause, neither of which will help here). But it can be done efficiently in two passes. The fact that the element is unique <Name>

inside <Record>

is key, as it allows us to use the table Record

as the lookup table for the second pass (i.e. when we get rows Artist

).

First you need to (well, you should) create UNIQUE INDEX

on Record (Name ASC)

. In my example below I am using UNIQUE CONSTRAINT

, but this is only because I used a table variable instead of a temp table to make it easier to rerun the example code (without having to use an explicit IF EXISTS DROP at the top). This index will help you complete the second pass.

The example uses OPENXML, as it is likely to be more efficient when using a function .nodes()

, since the same document must be traversed twice. The last parameter to the function OPENXML

, 2

indicates that the document "is based on the element" as the default parsing looking "Based on the attributes."

DECLARE @DocumentID INT, @ImportData XML;

SET @ImportData = N'
<Records>
  <Record>
    <Name>Best of Pop</Name>
    <Studio>ABC studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>John</ArtistName>
        <Age>36</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Jessica</ArtistName>
        <Age>20</Age>            
      </Artist>
    </Artists>
  </Record>
  <Record>
    <Name>Nursery rhymes</Name>
    <Studio>XYZ studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>Judy</ArtistName>
        <Age>10</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Rachel</ArtistName>
        <Age>15</Age>            
      </Artist>
    </Artists>
  </Record>
</Records>';


DECLARE @Record TABLE (RecordId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       Name NVARCHAR(400) UNIQUE,
                       Studio NVARCHAR(400));
DECLARE @Artist TABLE (ArtistId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                       RecordId INT NOT NULL,
                       ArtistName NVARCHAR(400), Age INT);

EXEC sp_xml_preparedocument @DocumentID OUTPUT, @ImportData;

-- First pass: extract "Record" rows
INSERT INTO @Record (Name, Studio)
   SELECT Name, Studio
   FROM   OPENXML (@DocumentID, N'/Records/Record', 2) 
             WITH (Name    NVARCHAR(400)  './Name/text()', 
                   Studio  NVARCHAR(400)  './Studio/text()');


-- Second pass: extract "Artist" rows
INSERT INTO @Artist (RecordId, ArtistName, Age)
   SELECT rec.RecordId, art.ArtistName, art.Age
   FROM   OPENXML (@DocumentID, N'/Records/Record/Artists/Artist', 2) 
             WITH (Name        NVARCHAR(400)  '../../Name/text()',
                   ArtistName  NVARCHAR(400)  './ArtistName/text()', 
                   Age         INT  './Age/text()') art
   INNER JOIN @Record rec
           ON rec.[Name] = art.[Name];


EXEC sp_xml_removedocument @DocumentID;
-------------------

SELECT * FROM @Record ORDER BY [RecordID];
SELECT * FROM @Artist ORDER BY [RecordID];

Literature:



EDIT:
With the new requirement to use a function .nodes()

instead OPENXML

, the following will work:

DECLARE @ImportData XML;

SET @ImportData = N'
<Records>
  <Record>
    <Name>Best of Pop</Name>
    <Studio>ABC studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>John</ArtistName>
        <Age>36</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Jessica</ArtistName>
        <Age>20</Age>            
      </Artist>
    </Artists>
  </Record>
  <Record>
    <Name>Nursery rhymes</Name>
    <Studio>XYZ studio</Studio>
    <Artists>
      <Artist>
        <ArtistName>Judy</ArtistName>
        <Age>10</Age>            
      </Artist> 
      <Artist>
        <ArtistName>Rachel</ArtistName>
        <Age>15</Age>            
      </Artist>
    </Artists>
  </Record>
</Records>';

IF (OBJECT_ID('tempdb..#Record') IS NOT NULL)
BEGIN
   DROP TABLE #Record;
END;
IF (OBJECT_ID('tempdb..#Artist') IS NOT NULL)
BEGIN
   DROP TABLE #Artist;
END;

CREATE TABLE #Record (RecordId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                      Name NVARCHAR(400) UNIQUE,
                      Studio NVARCHAR(400));
CREATE TABLE #Artist (ArtistId INT NOT NULL IDENTITY(1, 1) PRIMARY KEY,
                      RecordId INT NOT NULL,
                      ArtistName NVARCHAR(400),
                      Age INT);


-- First pass: extract "Record" rows
INSERT INTO #Record (Name, Studio)
   SELECT col.value(N'(./Name/text())[1]', N'NVARCHAR(400)') AS [Name],
          col.value(N'(./Studio/text())[1]', N'NVARCHAR(400)') AS [Studio]
   FROM   @ImportData.nodes(N'/Records/Record') tab(col);


-- Second pass: extract "Artist" rows
;WITH artists AS
(
   SELECT col.value(N'(../../Name/text())[1]', N'NVARCHAR(400)') AS [RecordName],
          col.value(N'(./ArtistName/text())[1]', N'NVARCHAR(400)') AS [ArtistName],
          col.value(N'(./Age/text())[1]', N'INT') AS [Age]
   FROM   @ImportData.nodes(N'/Records/Record/Artists/Artist') tab(col)
)
INSERT INTO #Artist (RecordId, ArtistName, Age)
   SELECT rec.RecordId, art.ArtistName, art.Age
   FROM artists art
   INNER JOIN #Record rec
           ON rec.[Name] = art.RecordName;

-- OR --
-- INSERT INTO #Artist (RecordId, ArtistName, Age)
   SELECT rec.RecordId,
          col.value(N'(./ArtistName/text())[1]', N'NVARCHAR(400)') AS [ArtistName],
          col.value(N'(./Age/text())[1]', N'INT') AS [Age]
   FROM   @ImportData.nodes(N'/Records/Record/Artists/Artist') tab(col)
   INNER JOIN #Record rec
           ON rec.Name = col.value(N'(../../Name/text())[1]', N'NVARCHAR(400)');

-------------------

SELECT * FROM #Record ORDER BY [RecordID];
SELECT * FROM #Artist ORDER BY [RecordID];

There are two options for inserting into #Artist

, shown above. The first uses CTEs to abstract the extraction of XML from an INSERT / SELECT query. The other is a simplified version, similar to your query in UPDATE 2 of the question.

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