XML In SQL Server

Introduction

• XML stands for Extensible Markup Language.
• XML was designed to store and transport data.
• XML was designed to be both human and machine readable.

Use For XML in SQL Server

• You can retrieve result as XML and then use the XML clause in the query.
• The "FOR XML" uses top-level queries and sub-queries.
• "FOR XML" is also used with a DML command.

There are four Models:

1. Raw
2. Explicit
3. Path
4. Auto

Description for Models

• Raw
  
  It generates a single <row> element as per row in the rowset that is returned by a select statement. It also uses nested "FOR XML" queries.
  
  
• Explicit
  
  You can mix attributes and elements in deciding the shape of XML. It requires a specific format for resulting format. This rowset format is then mapped into XML shape.
  
  
• Path
  
  The nested "FOR XML" query capability provides the flexibility. These models are for the execution of the query for which they are set. They do not affect the results of any subsequent query.
  
  
• Auto
  
  It generates a nested result, the Minimal control over the shape of XML data.

( Ref: MSDN).

All Models Examples

Firstly, create a table and insert data in the table

Step 1: Create a table.

You can create a table or use your existing table.


Figure 1.1

Step 2: Insert data in table.

Insert data of created table structure.


Figure 1.2

Step 3: Retrieve data in table.

You can see data is inserted from the table:


Figure 1.3

RAW


Figure 1.4

Simple used RAW

Output

Figure 1.5

Figure 1.5 - Used RAW with Elements.

Output
EXPLICIT


Figure 1.6

Figure 1.6 - Used Explicit Model

Output
PATH


Figure 1.7

Output

Figure 1.8

Figure 1.8 - Another way to use path.


Figure 1.9

Figure 1.9 - Example: used path as root element.

Auto


Figure 1.10

Figure 1.10 - Used as AUTO models.

Output

Figure 1.11

Note: Please find the attachment for code.