TSQL stored procedure and XQuery? - sql

Question

I want to write a stored procedure that queries XML files after I have input a certain string pattern to look for.
I'm already stuck at the input parameters, consider the following XML-document.
<root>
<container>
<element>A</element>
<option>1</option>
</container>
<container>
<element>B</element>
<option>-1</option>
</container>
<container>
<element>C</element>
</container>
</root>
What I want to achieve is find and output a certain pattern combining element-tag and option-tag to a table.
For example: EXEC search "A1,B-1,C" is the input string and would be true which then needs to be put in a table. But "A,B,C" would be false.
I'm not that great with TSQL, so I don't know how I could split or arrange the search pattern so that I could use this to work with both element-tag and option-tag and put them into variables or so.
EDIT: The code below I think is going in the right direction but I have another big issue.
I need to analyze each value of the pattern with a corresponding table.
I better give an example: Input is "A1,B-1,C" btw input length should be flexible.
In my existing table I have 4 columns with the following data:
ID| Value | Meaning | Info
1 | A | text | text
2 | A-1 | text | text
3 | A1 | text | text
4 | B | text | text
5 | B-1 | text | text
and so on...
Now somehow I need to check each single input-string with the value and output the input-string with both "Meaning" and "Info" column to another table.
With the example above I would have to find the sequence of "A1,B-1,C" and then output the corresponding text (including the string) of the table above to a new table.
So that it could look like this:
| Value | Meaning | Info
| A1 | text | text
| B-1 | text | text
| C | text | text
I don't know if I'm making it too complicated with the above table or if a CASE / IF-ELSE structure in the procedure would work better.
Does anyone know how this can be achieved?

Answer 1

It looks as if you're using the wrong tools for the job but if these are pretty firm constraints you're working against then you could use the following, for example:
drop table #xml
drop table #queryparams
declare #x xml
select #x = '<code><root><items><element>A</element><option>1</option></items><items><element>B</element><option>-1</option></items><items><element>C</element></items></root></code>'
create table #xml (element varchar(60), [option] int null)
insert into #xml
select code.item.value('(element)[1]', 'varchar(60)'),
code.item.value('(option)[1]', 'int')
from
#x.nodes('/code/root/items') AS code(item)
declare #queryParam varchar(60)
select #queryParam = 'A1,B-1,C'
create table #queryparams (element varchar(60), [option] int null)
insert into #queryparams
select left(data,1), RIGHT(data, len(data)-1)
from dbo.split(#queryParam,',')
if not exists (
select *
from #xml x
left join #queryparams q
on x.element = q.element
where q.[option] is null
)
select 1
else
select 0
As marc_s suggests you're better off with <element> and <option> tags inside a common tag. I've opted for the poorly named <items> in this case.
This solution is nasty enough to suggest the approach isn't quite right somehow.