Inferring Tables
When inferring a schema for a DataSet from an XML document, ADO.NET first determines which XML elements represent tables. The following XML structures result in a table for the DataSet schema:
Elements with attributes
Elements with child elements
Repeating elements
Elements with Attributes
Elements that have attributes specified in them result in inferred tables. For example, consider the following XML:
<DocumentElement>
<Element1 attr1="value1"/>
<Element1 attr1="value2">Text1</Element1>
</DocumentElement>
The inference process produces a table named "Element1."
DataSet: DocumentElement
Table: Element1
| attr1 | Element1_Text |
|---|---|
| value1 | |
| value2 | Text1 |
Elements with Child Elements
Elements that have child elements result in inferred tables. For example, consider the following XML:
<DocumentElement>
<Element1>
<ChildElement1>Text1</ChildElement1>
</Element1>
</DocumentElement>
The inference process produces a table named "Element1."
DataSet: DocumentElement
Table: Element1
| ChildElement1 |
|---|
| Text1 |
The document, or root, element result in an inferred table if it has attributes or child elements that are inferred as columns. If the document element has no attributes and no child elements that would be inferred as columns, the element is inferred as a DataSet. For example, consider the following XML:
<DocumentElement>
<Element1>Text1</Element1>
<Element2>Text2</Element2>
</DocumentElement>
The inference process produces a table named "DocumentElement."
DataSet: NewDataSet
Table: DocumentElement
| Element1 | Element2 |
|---|---|
| Text1 | Text2 |
Alternatively, consider the following XML:
<DocumentElement>
<Element1 attr1="value1" attr2="value2"/>
</DocumentElement>
The inference process produces a DataSet named "DocumentElement" that contains a table named "Element1."
DataSet: DocumentElement
Table: Element1
| attr1 | attr2 |
|---|---|
| value1 | value2 |
Repeating Elements
Elements that repeat result in a single inferred table. For example, consider the following XML:
<DocumentElement>
<Element1>Text1</Element1>
<Element1>Text2</Element1>
</DocumentElement>
The inference process produces a table named "Element1."
DataSet: DocumentElement
Table: Element1
| Element1_Text |
|---|
| Text1 |
| Text2 |