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Grabbing Certain Parts of XML Stored in DB - ASP.NET

In my database I have a column that stores XML data, the database items are accessed through my model. However I need to be able to access specific items within the XML column, and convert them into a string to be used on my web page, what's the best way of doing this?
Example:
<DATAROW AgreementNumber="0000000" LoanAmount="£0.00" LoanTerm="20"
Title="Miss" FirstName="Joe" LastName="Bloggs"/>

Store data of multiple parsed XML files - .NET

I've been working on a VB application which parses multiple XML files, and create an Excel file from them.
The main problem of this is that I am, simply, reading each line of each XML and outputs them to the Excel file when a specific node is found. I would like to know if exists any method to store the data from each element, just to use it once everything (all the XML files) have been parsed.
I was thinking about databases but I think this is excessive and unnecesary. Maybe you can give me some ideas in order to make it working.

System.Data.DataSet can be used as an "in memory database".
You can use a DataSet to store information in memory - a DataSet can contain multiple DataTables and you can add columns to those at runtime, even if there are already rows in the DataTable. So even if you don't know the XML node names ahead of time, you can add them as columns as they appear.
You can also use DataViews to filter the data inside the DataSet.
My typical way of pre-parsing XML is to create a two-column DataTable with the XPATH address of each node and its value. You can then do a second pass that matches XPATH addresses to your objects/dataset.

Reading a string formatted like XML

I have a string that is written out like an XML file. An example would look like this:
string = <Employees><EmployeeId>1</EmployeeId>< ... ></Employees>
I am saving this in a table because I wanted to audit changes, but I didn't want to have multiple tables for different audits. This is because it would record changes to things other than employees. So using an XML style string in the database seemed like a good suggestion.
Now to the real business. I want to check to make sure that there were actually changes to the employee because one could go into the edit page, change nothing, and click save. As of right now, the data would write to the DB and just clutter it up with non-changed data.
I'd like to be able to check if the XML styled string that is going to be saved is on the database, so if <employees><employeeid>###</employeeid> == "changes" and then see if the whole string equals the other. Basically, check the employeeId first because that won't change, and then check the string as a whole to see if there is any difference. I would have just checked the first n numbers, but the id number could have a length of 1 to 3.
Also, because it is styled as XML, is there an easy way to convert it to read it like an XML file and check that way?

Storing arbitrary data in a column is a form of denormalization. You can't really do much with it at a database level. However, SQL Server does have an XML column type. Entity Framework doesn't support mapping to/from an XML column, so it will simply treat your XML as a standard string. With this column type, though, you can write actual SQL queries against your XML using XPath expressions.
Your best bet, then, is to type your column as XML, and then write a stored procedure that performs the query you need. You can then utilize this stored procedure with Entity Framework.
For more information on the XML column type see: https://msdn.microsoft.com/en-us/library/ms190798(SQL.90).aspx

How do I read LookUp fields with multiple values in SharePoint?

Hi and thanks for looking!
Background
I have inherited an old .NET project based on SharePoint 2007 and have designed and external core library which merely accesses SP data, therefore making SP just a backend. Yes, I know it would be better to migrate to SQL, but the client doesn't agree.
The previous developers used a simple read method to read the data in a SP list:
SPList list = CurrentRootWeb.Lists["SomeListName"];
And then they access list properties through a dictionary of sorts (i.e. for each item in list, get item["SomeValue"]).
I am not skilled in SharePoint, so I don't know if this is the most efficient manner to go about accessing it's data.
Problem
How do I read LookUp fields with multiple values in SharePoint?
Every property they request seems to want a string in return. So item[SomeString] is okay, but item[SomeList] makes everything barf! I would have thought that a multi-value lookup list column comes in as a serialized or delimited string holding the selected values (example: "red;blue;green"). What am I missing?
Thanks!

If you are specifically interested in LookUp fields with multiple values not just MultiChoice feilds, then following code should help:
item.Fields["LookFieldName"].Type == SPFieldType.Lookup;
SPFieldLookup LookUpField = item.Fields["LookFieldName"] as SPFieldLookup;
if (LookUpField.AllowMultipleValues)
{
SPFieldLookupValueCollection valueCollection = item[Field.Id] as SPFieldLookupValueCollection;
string[] arrLookupValues = (from SPFieldLookupValue val in valueCollection select val.LookupValue).ToArray<string>();
}

For each of the SPFields in the list's fields, you need to test the field's Type.
If the type is SPFieldType.MultiChoice, then you cast the SPField to SPFieldChoice and access the Choices collection, which is a StringCollection.

Loading a lookup table from a database into a C# program - data structure?

I have a table full of id's,categories and weights that I need to reference in my program as I read in records that contain those categories. What is the most efficient method to read those from a database and put into a structure that I can reference?
The ID's (and possibly the names) would be unique
Data might look like:
ID,Category,Weight
1,Assignment,5
2,Test,10
3,Quiz,5
4,Review,3

Your best bet is to read in your table using a DataReader, and put each row into an object containing Category and Weight, then each object into a Dictionary.

If you're using a later version of .NET, you could always use Linq to just grab that data for you.

If you want to avoid a database hit to fetch static data, you can hard-code the values into a common class in your solution. A Dictionary collection would work fine here too.
The trade off of course is; 2 locations to manage for any possible future changes.