SQLFiddle for相同:根据@xQbert 建议的解决方案

SQLFiddle for the same: Solution as per @xQbert suggested

create table Temp (col1 xml)
go

insert into Temp (col1)
values('<qualifiers>
    <qualifier>
      <key>111</key>
      <message>a match was not found</message>
    </qualifier>
    <qualifier>
      <key>222</key>
      <message>a match was found</message>
    </qualifier>
    <qualifier>
      <key>333</key>
      <message>error</message>
    </qualifier>
  </qualifiers>')
go

SELECT
    STUFF((SELECT 
              ',' + fd.v.value('(.)[1]', 'varchar(50)')
           FROM 
              Temp
           CROSS APPLY
              col1.nodes('/qualifiers/qualifier/message') AS fd(v)
           FOR XML PATH('')
          ), 1, 1, '')