Using XML to serialize a SQL Query

[Bob]

Let me state up front that I know very little about XML. My experience is
pretty much limited using the XML Serializer to serialize a user preferences
class to a file and back again.

I'm writing a rules engine for an application that basically involves
allowing the user to enter the the WHERE clause for a SQL Server query that
becomes the rule. The rules will be stored in a SQL Server database and the
user will be able to make changes to the rules. The rules are entered through
a non-freeform interface, so I don't have to try and parse the rule after the
user enters it. However, when I retrieve the rule from the database I will
need to identify the parts of the rule to properly repopulate the interface.

My first thought was that i would have to create my own syntax to represent
the rule and write code to parse the result but then I thought XML was
supposed to be good at that sort of thing. So I started reading about XSD
schemas hoping to create something that I could use to create an string
containing the rule that I could write into the database and the opposite.

I started trying to create an XSD schema for the rules and then I looked at
the recursive definition of a SQL WHERE clause and figured I'd better ask for
advice.

I did a Google search for an XSD schema for a SQL Server query and came up
with nothing.

Is XML the correct tool for my problem?

Does anyone know where I can get an XSD schema for either a SQL query or the
WHERE clause?

How do I handle the recursive definition of the WHERE clause in an XSD schema?

Is there a better way to approach my problem?

Thanks,

Bob

[Kevin Yu [MSFT]]

Hi Bob,

First of all, I would like to confirm my understanding of your issue. From
your description, I understand that you need to parse the WHERE clause
yourself. If there is any misunderstanding, please feel free to let me know.

As far as I know, XML and XSD are not the right choice for us to achieve
this. Instead, I recommend you use Regular Expressions.

Regular expressions provide a powerful, flexible, and efficient method for
processing text. The extensive pattern-matching notation of regular
expressions allows you to quickly parse large amounts of text to find
specific character patterns; to extract, edit, replace, or delete text
substrings; or to add the extracted strings to a collection in order to
generate a report. For many applications that deal with strings (such as
HTML processing, log file parsing, and HTTP header parsing), regular
expressions are an indispensable tool.

In .NET framework, we have classes that can manipulate on Regular
Expressions such as Regex under namespace System.Text.RegularExpressions.

For more information, please check the following links:

http://msdn.microsoft.com/library/de...us/cpguide/htm
l/cpconCOMRegularExpressions.asp

http://msdn.microsoft.com/library/de...us/cpref/html/
frlrfSystemTextRegularExpressionsRegexClassTopic.a sp

HTH.

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."

[Kevin Yu [MSFT]]

Sorry, Bob, I may not understand your problem quite well. Thanks to Dino,
for providing such useful information.

Also thanks to Bob for sharing your experience with all the people here. If
you have any questions, please feel free to post them in the community.

Kevin Yu
=======
"This posting is provided "AS IS" with no warranties, and confers no
rights."