Querying XML colum for values - sql

Question

I have a SQL Server table with an XML column, and it contains data something like this:
<Query>
<QueryGroup>
<QueryRule>
<Attribute>Integration</Attribute>
<RuleOperator>8</RuleOperator>
<Value />
<Grouping>OrOperator</Grouping>
</QueryRule>
<QueryRule>
<Attribute>Integration</Attribute>
<RuleOperator>5</RuleOperator>
<Value>None</Value>
<Grouping>AndOperator</Grouping>
</QueryRule>
</QueryGroup>
</Query>
Each QueryRule will only have one Attribute, but each QueryGroup can have many QueryRules. Each Query can also have many QueryGroups.
I need to be able to pull all records that have one or more QueryRule with a certain attribute and value.
SELECT *
FROM QueryBuilderQueries
WHERE [the xml contains any value=X where the attribute is either Y or Z]
I've worked out how to check a specific QueryRule, but not "any".
SELECT
Query
FROM
QueryBuilderQueries
WHERE
Query.value('(/Query/QueryGroup/QueryRule/Value)[1]', 'varchar(max)') like 'UserToFind'
AND Query.value('(/Query/QueryGroup/QueryRule/Attribute)[1]', 'varchar(max)') in ('FirstName', 'LastName')

Answer 1

You can use two exist(). One to check the value and one to check Attribute.
select Q.Query
from dbo.QueryBuilderQueries as Q
where Q.Query.exist('/Query/QueryGroup/QueryRule/Value/text()[. = "UserToFind"]') = 1 and
Q.Query.exist('/Query/QueryGroup/QueryRule/Attribute/text()[. = ("FirstName", "LastName")]') = 1
If you really want the like equivalence when you search for a Value you can use contains().
select Q.Query
from dbo.QueryBuilderQueries as Q
where Q.Query.exist('/Query/QueryGroup/QueryRule/Value/text()[contains(., "UserToFind")]') = 1 and
Q.Query.exist('/Query/QueryGroup/QueryRule/Attribute/text()[. = ("FirstName", "LastName")]') = 1

Answer 2

According to http://technet.microsoft.com/pl-pl/library/ms178030%28v=sql.110%29.aspx
"The XQuery must return at most one value"
If you are quite certain that for example your XML has let's say maximum 10 QueryRules you could maybe use WHILE to loop everything while droping your results into temporary table?
maybe below can help you anyway
CREATE TABLE #temp(
Query type)
DECLARE #i INT
SET #i = 1
WHILE #i >= 10
BEGIN
INSERT INTO #temp
SELECT
Query
FROM QueryBuilderQueries
WHERE Query.value('(/Query/QueryGroup/QueryRule/Value)[#i]', 'varchar(max)') LIKE 'UserToFind'
AND Query.value('(/Query/QueryGroup/QueryRule/Attribute)[#i]', 'varchar(max)') IN ('FirstName', 'LastName')
#i = #i + 1
END
SELECT
*
FROM #temp

Answer 3

It's a pity that the SQL Server (I'm using 2008) does not support some XQuery functions related to string such as fn:matches, ... If it supported such functions, we could query right inside XQuery expression to determine if there is any. However we still have another approach. That is by turning all the possible values into the corresponding SQL row to use the WHERE and LIKE features of SQL for searching/filtering. After some experiementing with the nodes() method (used on an XML data), I think it's the best choice to go:
select *
from QueryBuilderQueries
where exists( select *
from Query.nodes('//QueryRule') as v(x)
where LOWER(v.x.value('(Attribute)[1]','varchar(max)'))
in ('firstname','lastname')
and v.x.value('(Value)[1]','varchar(max)') like 'UserToFind')