How can I query a value in SQL Server XML column

问题

I have following XML stored in a XML column (called Roles) in a SQL Server database.

<root>
   <role>Alpha</role>
   <role>Beta</role>
   <role>Gamma</role>
</root>

I'd like to list all rows that have a specific role in them. This role passed by parameter.

回答1:

select
  Roles
from
  MyTable
where
  Roles.value('(/root/role)[1]', 'varchar(max)') like 'StringToSearchFor'

These pages will show you more about how to query XML in T-SQL:

Querying XML fields using t-sql

Flattening XML Data in SQL Server

EDIT

After playing with it a little bit more, I ended up with this amazing query that uses CROSS APPLY. This one will search every row (role) for the value you put in your like expression...

Given this table structure:

create table MyTable (Roles XML)

insert into MyTable values
('<root>
   <role>Alpha</role>
   <role>Gamma</role>
   <role>Beta</role>
</root>')

We can query it like this:

select * from 

(select 
       pref.value('(text())[1]', 'varchar(32)') as RoleName
from 
       MyTable CROSS APPLY

       Roles.nodes('/root/role') AS Roles(pref)
)  as Result

where RoleName like '%ga%'

You can check the SQL Fiddle here: http://sqlfiddle.com/#!3/ae0d5/13

回答2:

declare @T table(Roles xml)

insert into @T values
('<root>
   <role>Alpha</role>
   <role>Beta</role>
   <role>Gamma</role>
</root>')

declare @Role varchar(10)

set @Role = 'Beta'

select Roles
from @T
where Roles.exist('/root/role/text()[. = sql:variable("@Role")]') = 1

If you want the query to work as where col like '%Beta%' you can use contains

declare @T table(Roles xml)

insert into @T values
('<root>
   <role>Alpha</role>
   <role>Beta</role>
   <role>Gamma</role>
</root>')

declare @Role varchar(10)

set @Role = 'et'

select Roles
from @T
where Roles.exist('/root/role/text()[contains(., sql:variable("@Role"))]') = 1

回答3:

if your field name is Roles and table name is table1 you can use following to search

DECLARE @Role varchar(50);
SELECT * FROM table1
WHERE Roles.exist ('/root/role = sql:variable("@Role")') = 1

回答4:

I came up with a simple work around below which is easy to remember too :-)

select * from  
(select cast (xmlCol as varchar(max)) texty
 from myTable (NOLOCK) 
) a 
where texty like '%MySearchText%'

回答5:

You could do the following

declare @role varchar(100) = 'Alpha'
select * from xmltable where convert(varchar(max),xmlfield) like '%<role>'+@role+'</role>%'

Obviously this is a bit of a hack and I wouldn't recommend it for any formal solutions. However I find this technique very useful when doing adhoc queries on XML columns in SQL Server Management Studio for SQL Server 2012.

回答6:

I used the below statement to retrieve the values in the XML in the Sql table

with xmlnamespaces(default 'http://test.com/2008/06/23/HL.OnlineContract.ValueObjects')
select * from (
select
            OnlineContractID,
            DistributorID,
            SponsorID,
    [RequestXML].value(N'/OnlineContractDS[1]/Properties[1]/Name[1]', 'nvarchar(30)') as [Name]
   ,[RequestXML].value(N'/OnlineContractDS[1]/Properties[1]/Value[1]', 'nvarchar(30)') as [Value]
     ,[RequestXML].value(N'/OnlineContractDS[1]/Locale[1]', 'nvarchar(30)') as [Locale]
from [OnlineContract]) as olc
where olc.Name like '%EMAIL%' and olc.Value like '%EMAIL%' and olc.Locale='UK EN'

回答7:

Useful tip. Query a value in SQL Server XML column (XML with namespace)

e.g.

Table [dbo].[Log_XML] contains columns Parametrs (xml),TimeEdit (datetime)

e.g. XML in Parametrs:

<ns0:Record xmlns:ns0="http://Integration"> 
<MATERIAL>10</MATERIAL> 
<BATCH>A1</BATCH> 
</ns0:Record>

e.g. Query:

select
 Parametrs,TimeEdit
from
 [dbo].[Log_XML]
where
 Parametrs.value('(//*:Record/BATCH)[1]', 'varchar(max)') like '%A1%'
 ORDER BY TimeEdit DESC

来源：https://stackoverflow.com/questions/10344553/how-can-i-query-a-value-in-sql-server-xml-column

标签

sql

sql-server

xml

xquery