Question

我正在尝试通过将其连接到条件表来找到对XML字符串执行接受/拒绝的方法。我现在有一个“过滤器”工作，但想写它以便它可以过滤2个或更多。

这是与两者中的一个匹配的代码。如果匹配，它将过滤字符串。我想做的是让它必须与BOTH匹配，同时仍然保留单条件的选项

CREATE TABLE #filter (exclusion_type CHAR(1), excluded_value varchar(10))
INSERT INTO #filter VALUES ('B','boy')
INSERT INTO #filter VALUES ('C','cat')

DECLARE @data XML
SELECT @data = '<A><B>boy</B><C>cat</C></A>'
SELECT * FROM (SELECT CONVERT(VARCHAR(128),node.query('fn:local-name(.)')) AS NodeName, CONVERT(VARCHAR(MAX),node.query('./text()')) AS NodeValue
FROM @data.nodes(N'//*') T(node))xml_shred

IF NOT EXISTS 
(SELECT * FROM (SELECT CONVERT(VARCHAR(128),node.query('fn:local-name(.)')) AS NodeName, CONVERT(VARCHAR(MAX),node.query('./text()')) AS NodeValue
FROM @data.nodes(N'//*') T(node)) xml_shred
INNER JOIN #filter
ON   (nodename = exclusion_type AND nodevalue LIKE excluded_value)
)
select 'record would be inserted '
ELSE select 'record was filtered'

以下是我目前如何过滤它们的方法。丑陋且不可扩展。

IF NOT EXISTS 
(SELECT * FROM (SELECT CONVERT(VARCHAR(128),node.query('fn:local-name(.)')) AS NodeName, CONVERT(VARCHAR(MAX),node.query('./text()')) AS NodeValue
FROM @data.nodes(N'//*') T(node)) xml_shred
INNER JOIN #filter
ON   (nodename = exclusion_type AND nodevalue LIKE excluded_value)
)
--combination filters don't easily work within that xml_shred
and not(
        @data.value('(/A/B)[1]', 'varchar(128)') = 'boy'
        AND 
        @data.value('(/A/C)[1]', 'varchar(128)')='cat'
        )

select 'record would be inserted '
ELSE select 'record was filtered'

我唯一的其他想法：

将#filter表中的记录链接在一起的某种GUID，然后是#filtertable的GROUP BY上的内连接，按GUID分组并使用SUM匹配记录数。
使用分号分割#filter行，然后使用CTE或其他东西伪造层次结构并从那里开始工作。

Mikael建议的代码更改

CREATE TABLE #filter
    (
      exclusion_set SMALLINT,
      exclusion_type CHAR(1) ,
      excluded_value VARCHAR(10)
    )
INSERT  INTO #filter
VALUES  (1, 'B', 'boy')
INSERT  INTO #filter
VALUES  (1, 'C', 'cat')
INSERT  INTO #filter
VALUES  (2, 'D', 'dog' )

DECLARE @data XML
SELECT  @data = '<A><B>boy</B><C>cat</C></A>'
IF NOT EXISTS(
SELECT * FROM 
(
select COUNT(*) AS match_count, exclusion_set
              from #filter as F
              where exists (
                           select *
                           from (
                                select X.N.value('local-name(.)', 'varchar(128)') as     NodeName,
                                       X.N.value('./text()[1]', 'varchar(max)') as     NodeValue
                                from @data.nodes('//*') as X(N)
                                ) T
                           where T.NodeName = F.exclusion_type and
                                 T.NodeValue like F.excluded_value 
                           )
GROUP BY exclusion_set
) matches_per_set
INNER JOIN 
(SELECT COUNT(*) AS total_count, exclusion_set FROM #filter GROUP BY exclusion_set)     grouped_set
ON match_count = total_count
AND grouped_set.exclusion_set = matches_per_set.exclusion_set
)

Answer 1

if not exists (
              select *
              from #filter as F
              where exists (
                           select *
                           from (
                                select X.N.value('local-name(.)', 'varchar(128)') as NodeName,
                                       X.N.value('./text()[1]', 'varchar(max)') as NodeValue
                                from @data.nodes('//*') as X(N)
                                ) T
                           where T.NodeName = F.exclusion_type and
                                 T.NodeValue like F.excluded_value 
                           )
              having count(*) = (select count(*) from #filter)
              )
  select 'record would be inserted '
else
  select 'record was filtered'

Answer 2

因为如果我没有将某些东西标记为答案，我显然会感到害怕，我会从上面包括我的。非常感谢Mikael Eriksson的帮助。他的XML碎片比我的快，并且通过添加“exclusion_set”字段（char（2）使其明显不是IDENTITY或主键），我可以进行多次检查。如果集合中的所有条件都匹配，则过滤记录。

CREATE TABLE #filter
    (
      exclusion_set CHAR(2),
      exclusion_type CHAR(1) ,
      excluded_value VARCHAR(10)
    )
INSERT  INTO #filter
VALUES  ('aa', 'B', 'boy')
INSERT  INTO #filter
VALUES  ('aa', 'C', 'cat')
INSERT  INTO #filter
VALUES  ('ab', 'D', 'dog' )

DECLARE @data XML
SELECT  @data = '<A><B>boy</B><C>cat</C></A>'
IF NOT EXISTS(
SELECT * FROM 
(
select COUNT(*) AS match_count, exclusion_set
              from #filter as F
              where exists (
                           select *
                           from (
                                select X.N.value('local-name(.)', 'varchar(128)') as     NodeName,
                                       X.N.value('./text()[1]', 'varchar(max)') as     NodeValue
                                from @data.nodes('//*') as X(N)
                                ) T
                           where T.NodeName = F.exclusion_type and
                                 T.NodeValue like F.excluded_value 
                           )
GROUP BY exclusion_set
) matches_per_set
INNER JOIN 
(SELECT COUNT(*) AS total_count, exclusion_set FROM #filter GROUP BY exclusion_set)     grouped_set
ON match_count = total_count
AND grouped_set.exclusion_set = matches_per_set.exclusion_set


 )
select 'record would be inserted '
else
  select 'record was filtered'

t-sql：在多个条件下动态过滤XML？

2 个答案: