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含与不含之间有显著差异?

containstable contains full-text-search tsql

Jagd Dai · 技术社区 · 14 年前

我在启用了文件流的varchar(max)类型的列上创建了全文索引。文件流包含JPG、TIF、PDF和XML等数据(尽管我认为这与问题基本无关)。

我创建了两个查询,允许我搜索索引。

全文搜索1--

select
      parentObj.ObjectID as 'GroupingID',
      parentObj.Name as 'Grouping',
      childObj.ObjectID as 'FileObjID', 
      childObj.Name as 'FileName',
      fs.FileStreamID
    from dbo.dat_FileStream fs
    inner join dbo.dat_Object childObj
        on fs.ObjectID = childObj.ObjectID
    inner join dbo.dat_Collection c
        on fs.ObjectID = c.ObjectID
    inner join dbo.dat_Object parentObj
        on c.ParentID = parentObj.ObjectID
    where contains(FileStreamData, @srchTerm)
        and parentObj.ObjectTypeID = 1
    ORDER BY 'Grouping'

全文搜索2--

select
      KEY_TBL.RANK,
      parentObj.ObjectID as 'GroupingID',
      parentObj.Name as 'Grouping',
      childObj.ObjectID as 'FileObjID',
      childObj.Name as 'FileName',
      fs.FileStreamID
    from dbo.dat_FileStream fs
    inner join containstable(dbo.dat_FileStream, FileStreamData, @srchTerm, 1000) as KEY_TBL
        on fs.FileStreamID = KEY_TBL.[KEY]
    inner join dbo.dat_Object childObj
        on fs.ObjectID = childObj.ObjectID
    inner join dbo.dat_Collection c
        on fs.ObjectID = c.ObjectID
    inner join dbo.dat_Object parentObj
        on c.ParentID = parentObj.ObjectID
    where parentObj.ObjectTypeID = 1
    ORDER BY 'Grouping'

两个全文搜索的唯一显著区别是query 1使用contains,query 2使用containstable。

我的问题是这两个查询并不总是产生相同的结果。例如,如果我搜索短语“独立承包商”,查询1将生成10个不同文档(PDF和XML)的结果集,而查询2将只生成6个结果集。这似乎就是规则:查询1总是比查询2产生更多的结果,而查询2总是产生与查询1完全相同的结果。

查询1-搜索“独立承包商”得出:

4262    AAA-00-12   4561    AAA-00-12.pdf   4235
4316    AAA-00-15   4753    AAA-00-15.pdf   4427
4316    AAA-00-15   4754    AAA-00-15.xml   4428
3873    AAA-00-19   4784    AAA-00-19.pdf   4458
3903    AAA-00-22   6795    AAA-00-22.pdf   6459
3953    AAA-00-24   6899    AAA-00-24.pdf   6563
3953    AAA-00-24   6900    AAA-00-24.xml   6564
4842    AAA-00-9    4905    AAA-00-9.pdf    4577
4842    AAA-00-9    4906    AAA-00-9.xml    4578
4057    AAA-0001    4260    AAA-0001.pdf    3936

查询2-搜索“独立承包商”得出:

19  4262    AAA-00-12   4561    AAA-00-12.pdf   4235
126 4316    AAA-00-15   4754    AAA-00-15.xml   4428
126 4316    AAA-00-15   4753    AAA-00-15.pdf   4427
116 3873    AAA-00-19   4784    AAA-00-19.pdf   4458
125 3903    AAA-00-22   6795    AAA-00-22.pdf   6459
57  3953    AAA-00-24   6900    AAA-00-24.xml   6564
57  3953    AAA-00-24   6899    AAA-00-24.pdf   6563

1 回复 | 直到 14 年前

Remus Rusanu 14 年前

CONTAINSTABLE :

top_n_by_rank

指定只有排名最高的匹配项,按降序排列, 返回。仅当指定整数值n。 如果排名靠前的与其他的相结合参数,查询可能返回行数少于行数这实际上符合所有谓词。

尝试不带上衣跑步,看看是否匹配 CONTAINS .