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    <p>Stumbled across this question whilst having a very similar problem, I'd been running a query processing a 7.5MB XML file (~approx 10,000 nodes) for around 3.5~4 hours before finally giving up.</p> <p>However, after a little more research I found that having typed the XML using a schema and created an XML Index (I'd bulk inserted into a table) the same query completed in ~ 0.04ms.</p> <p>How's that for a performance improvement!</p> <p>Code to create a schema:</p> <pre><code>IF EXISTS ( SELECT * FROM sys.xml_schema_collections where [name] = 'MyXmlSchema') DROP XML SCHEMA COLLECTION [MyXmlSchema] GO DECLARE @MySchema XML SET @MySchema = ( SELECT * FROM OPENROWSET ( BULK 'C:\Path\To\Schema\MySchema.xsd', SINGLE_CLOB ) AS xmlData ) CREATE XML SCHEMA COLLECTION [MyXmlSchema] AS @MySchema GO </code></pre> <p>Code to create the table with a typed XML column:</p> <pre><code>CREATE TABLE [dbo].[XmlFiles] ( [Id] [uniqueidentifier] NOT NULL, -- Data from CV element [Data] xml(CONTENT dbo.[MyXmlSchema]) NOT NULL, CONSTRAINT [PK_XmlFiles] PRIMARY KEY NONCLUSTERED ( [Id] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] </code></pre> <p>Code to create Index</p> <pre><code>CREATE PRIMARY XML INDEX PXML_Data ON [dbo].[XmlFiles] (Data) </code></pre> <p>There are a few things to bear in mind though. SQL Server's implementation of Schema doesn't support xsd:include. This means that if you have a schema which references other schema, you'll have to copy all of these into a single schema and add that.</p> <p>Also I would get an error:</p> <pre><code>XQuery [dbo.XmlFiles.Data.value()]: Cannot implicitly atomize or apply 'fn:data()' to complex content elements, found type 'xs:anyType' within inferred type 'element({http://www.mynamespace.fake/schemas}:SequenceNumber,xs:anyType) ?'. </code></pre> <p>if I tried to navigate above the node I had selected with the nodes function. E.g.</p> <pre><code>SELECT ,C.value('CVElementId[1]', 'INT') AS [CVElementId] ,C.value('../SequenceNumber[1]', 'INT') AS [Level] FROM [dbo].[XmlFiles] CROSS APPLY [Data].nodes('/CVSet/Level/CVElement') AS T(C) </code></pre> <p>Found that the best way to handle this was to use the OUTER APPLY to in effect perform an "outer join" on the XML.</p> <pre><code>SELECT ,C.value('CVElementId[1]', 'INT') AS [CVElementId] ,B.value('SequenceNumber[1]', 'INT') AS [Level] FROM [dbo].[XmlFiles] CROSS APPLY [Data].nodes('/CVSet/Level') AS T(B) OUTER APPLY B.nodes ('CVElement') AS S(C) </code></pre> <p>Hope that that helps someone as that's pretty much been my day.</p>
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    1. POThe Best Way to shred XML data into SQL Server database columns
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    1. USLuke Girvin
    1. USDan
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    1. POThe Best Way to shred XML data into SQL Server database columns
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    1. COGreat answer Dan, could you elaborate on how you map the xml nodes to columns in a table?
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    2. COHey longhairedsi, I'm not sure that I've properly understood your question. Do you mean inserting specific parts of an XML document into table columns or as I have above inserting the entire document into a single column and then using a select statement and the .nodes and .value functions (and the xpath syntax) to get the data out in a tabular format?
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    3. COI think I may have understood your answer :) I thought you were adding the xml to a column as a temporary location before shredding to existing table columns (e.g INSERT INTO xxx FROM XmlFiles.Data) or such like. I was looking for the most performant way to shread xml to existing columns, I think with a little work your solution would do that job nicely.
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