SQL Server 匹配词组和排序相关性的最佳方法

Question

根据参数中单词的数量（计数）/匹配对 sql varchar 列进行排名的最佳方法是什么，有四个不同的唯一标准。这可能不是一个微不足道的问题，但我面临的挑战是使用我的标准根据“最佳匹配”对行进行排序。

列：描述 varchar(100) 参数：@MyParameter varchar(100)

具有此顺序偏好的输出：

• 完全匹配（整个字符串匹配）- 总是在前
• 开头（根据匹配的参数长度递减）
• 在匹配词数相同的情况下，连续词排名更高的词数排名
• 单词匹配任何地方（不连续）

单词可能不完全匹配，因为允许并且很可能单词的部分匹配，应将出租人值应用于部分单词以进行排名但不是关键的（pot 将匹配每个：pot、potter、potholder、depot、depotting for实例）。以其他单词匹配开头的排名应高于没有后续匹配的排名，但这不是交易杀手/超级重要。

我想要一种方法来对列“以”参数中的值“开始”的位置进行排名。假设我有以下字符串：

'This is my value string as a test template to rank on.'

在第一种情况下，我希望在存在最多字数的列/行中获得排名。

在开始时根据出现次数（最佳匹配）排名第二：

'This is my string as a test template to rank on.' - first
'This is my string as a test template to rank on even though not exact.'-second
'This is my string as a test template to rank' - third
'This is my string as a test template to' - next
'This is my string as a test template' - next etc.

其次：（可能是第一组（开头）之后的第二组/第二组数据 - 这是需要的

我想按@MyParameter 中出现在@MyParameter 中的单词数对行进行排名（排序），其中连续单词的排名高于单独的相同计数。

因此，对于上面的示例字符串，'is my string as shown' 的排名将高于'is not my other string as'，因为连续字符串（单词一起）的“更好匹配”与相同的单词数。匹配度较高的行（出现的字数）将按降序排列最佳匹配。

如果可能，我想在单个查询中执行此操作。

结果中不应出现任何行。

出于性能考虑，表中的行数不会超过 10,000 行。

表中的值是相当静态的，变化不大，但并非完全如此。

我目前无法更改结构，但稍后会考虑（如单词/短语表）

为了使这稍微复杂一些，单词列表位于两个表中 - 但我可以为此创建一个视图，但是一个表结果（较小的列表）应该先于第二个出现，给定相同匹配的较大数据集结果- 这些表以及表中都会有重复项，我只想要不同的值。选择 DISTINCT 并不容易，因为我想返回一个列（sourceTable），这很可能使行不同，在这种情况下，只能从第一个（较小的）表中选择，但需要所有其他列 DISTINCT（不要考虑“独特”评估中的列。

表格中的伪列：

procedureCode   VARCHAR(50),
description VARCHAR(100), -- this is the sort/evaluation column
category    VARCHAR(50),
relvu       VARCHAR(50),
charge  VARCHAR(15),
active  bit
sourceTable   VARCHAR(50) - just shows which table it comes from of the two

不存在像 ID 列这样的唯一索引

匹配不在要排除的第三个表中 SELECT * FROM (select * from tableone where procedureCode not in (select procedureCode from tablethree)) UNION ALL (select * from tabletwo where procedureCode not in (select procedureCode from tablethree))

编辑：为了解决这个问题，我创建了一个表值参数，如下所示：

0       Gastric Intubation & Aspiration/Lavage, Treatmen
1       Gastric%Intubation%Aspiration%Lavage%Treatmen
2       Gastric%Intubation%Aspiration%Lavage
3       Gastric%Intubation%Aspiration
4       Gastric%Intubation
5       Gastric
6       Intubation%Aspiration%Lavage%Treatmen
7       Intubation%Aspiration%Lavage
8       Intubation%Aspiration
9       Intubation
10      Aspiration%Lavage%Treatmen
11      Aspiration%Lavage
12      Aspiration
13      Lavage%Treatmen
14      Lavage
15      Treatmen

实际短语在第 0 行的位置

这是我目前的尝试：

CREATE PROCEDURE [GetProcedureByDescription]
(   
        @IncludeMaster  BIT,
        @ProcedureSearchPhrases CPTFavorite READONLY

)
AS

    DECLARE @myIncludeMaster    BIT;

    SET @myIncludeMaster = @IncludeMaster;

    CREATE TABLE #DistinctMatchingCpts
    (
    procedureCode   VARCHAR(50),
    description     VARCHAR(100),
    category        VARCHAR(50),
    rvu     VARCHAR(50),
    charge      VARCHAR(15),
    active      VARCHAR(15),
    sourceTable   VARCHAR(50),
    sequenceSet VARCHAR(2)
    )

    IF @myIncludeMaster = 0
        BEGIN -- Excluding master from search   
          INSERT INTO #DistinctMatchingCpts (sourceTable, procedureCode, description    ,   category  ,charge, active, rvu, sequenceSet
) 
      SELECT DISTINCT sourceTable, procedureCode, description, category ,charge, active, rvu, sequenceSet
          FROM (
                  SELECT TOP 1
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''01'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] = PP.[LEVEL]
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)
                  ORDER BY PP.CODE

          UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM([CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable, 
                      ''02'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] LIKE PP.[LEVEL] + ''%''
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

          UNION ALL

            SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''03'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] LIKE ''%'' + PP.[LEVEL] + ''%''
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

            ) AS CPTS
            ORDER BY 
                 procedureCode, sourceTable, [description]
        END -- Excluded master from search
    ELSE
        BEGIN -- Including master in search, but present favorites before master for each code
            -- Get matching procedures, ordered by code, source (favorites first), and description.
            -- There probably will be procedures with duplicated code+description, so we will filter
            -- duplicates shortly.
      INSERT INTO #DistinctMatchingCpts (sourceTable, procedureCode, description    ,   category  ,charge, active, rvu, sequenceSet) 
      SELECT DISTINCT sourceTable, procedureCode, description, category ,charge, active, rvu, sequenceSet
          FROM (
                  SELECT TOP 1
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''00'' AS sequenceSet
                FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] = PP.[LEVEL]
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)
                  ORDER BY PP.CODE

                  UNION ALL

                  SELECT TOP 1
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[CATEGORY])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      COALESCE(CASE [ACTIVE] WHEN 1 THEN ''True'' WHEN 0 THEN ''False'' WHEN '''' THEN ''False'' ELSE ''False'' END,''True'') AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''2MasterCPT'' AS sourceTable,
                      ''00'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [MASTERCPT] AS CPT
                      ON CPT.[LEVEL] = PP.[LEVEL]
                  WHERE 
                      CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)
                  ORDER BY PP.CODE

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''01'' AS sequenceSet
                FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] = PP.[LEVEL]
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[CATEGORY])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      COALESCE(CASE [ACTIVE] WHEN 1 THEN ''True'' WHEN 0 THEN ''False'' WHEN '''' THEN ''False'' ELSE ''False'' END,''True'') AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''2MasterCPT'' AS sourceTable,
                      ''01'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [MASTERCPT] AS CPT
                      ON CPT.[LEVEL] = PP.[LEVEL]
                  WHERE 
                      CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

                  UNION ALL

                  SELECT TOP 1
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''02'' AS sequenceSet
                FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] LIKE PP.[LEVEL] + ''%''
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)
                  ORDER BY PP.CODE

                  UNION ALL

                  SELECT TOP 1
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[CATEGORY])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      COALESCE(CASE [ACTIVE] WHEN 1 THEN ''True'' WHEN 0 THEN ''False'' WHEN '''' THEN ''False'' ELSE ''False'' END,''True'') AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''2MasterCPT'' AS sourceTable,
                      ''02'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [MASTERCPT] AS CPT
                      ON CPT.[LEVEL] LIKE PP.[LEVEL] + ''%''
                  WHERE 
                      CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)
                  ORDER BY PP.CODE

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''03'' AS sequenceSet
                FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] LIKE PP.[LEVEL] + ''%''
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[CATEGORY])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      COALESCE(CASE [ACTIVE] WHEN 1 THEN ''True'' WHEN 0 THEN ''False'' WHEN '''' THEN ''False'' ELSE ''False'' END,''True'') AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''2MasterCPT'' AS sourceTable,
                      ''03'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [MASTERCPT] AS CPT
                      ON CPT.[LEVEL] LIKE PP.[LEVEL] + ''%''
                  WHERE 
                      CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[COMBO])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      ''True'' AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''0CPTMore'' AS sourceTable,
                      ''04'' AS sequenceSet
                FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [CPTMORE] AS CPT
                      ON CPT.[LEVEL] LIKE ''%'' + PP.[LEVEL] + ''%''
                  WHERE 
                      (CPT.[COMBO] IS NULL OR CPT.[COMBO] NOT IN (''Editor'',''MOD'',''CATEGORY'',''Types'',''Bundles''))
                      AND CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

                  UNION ALL

                  SELECT 
                      LTRIM(RTRIM(CPT.[CODE])) AS procedureCode, 
                      LTRIM(RTRIM(CPT.[LEVEL])) AS description, 
                      LTRIM(RTRIM(CPT.[CATEGORY])) AS category,
                      LTRIM(RTRIM(CPT.[CHARGE])) AS charge,
                      COALESCE(CASE [ACTIVE] WHEN 1 THEN ''True'' WHEN 0 THEN ''False'' WHEN '''' THEN ''False'' ELSE ''False'' END,''True'') AS active,
                      LTRIM(RTRIM([RVU])) AS rvu,
                      ''2MasterCPT'' AS sourceTable,
                      ''04'' AS sequenceSet
                  FROM 
                    @ProcedureSearchPhrases PP
                    INNER JOIN  [MASTERCPT] AS CPT
                      ON CPT.[LEVEL] LIKE ''%'' + PP.[LEVEL] + ''%''
                  WHERE 
                      CPT.[CODE] IS NOT NULL
                      AND CPT.[CODE] NOT IN (''0'', '''')
                    AND CPT.[CODE] NOT IN (SELECT CPTE.[CODE] FROM CPT AS CPTE WHERE CPTE.[CODE] IS NOT NULL)

             ) AS CPTS 

            ORDER BY 
                 sequenceSet, sourceTable, [description]

        END

        /* Final select - uses artificial ordering from the insertion ORDER BY */
        SELECT procedureCode, description,  category, rvu, charge, active FROM
        ( 
        SELECT TOP 500 *-- procedureCode, description,  category, rvu, charge, active
        FROM #DistinctMatchingCpts
        ORDER BY sequenceSet, sourceTable, description

        ) AS CPTROWS

        DROP TABLE #DistinctMatchingCpts

但是，这不符合单词计数的最佳匹配标准（如样本中的第 1 行值），该标准应匹配从该行中找到的最佳（最多）单词计数。

如果有区别，我可以完全控制表值参数的形式/格式。

如果有用，我会将此结果返回给 c# 程序。

Answer 1

您需要能够拆分字符串才能解决此问题。 I prefer the number table approach to split a string in TSQL

为了使我的以下代码（以及我的拆分功能）正常工作，您需要执行此一个时间表设置：

SELECT TOP 10000 IDENTITY(int,1,1) AS Number
    INTO Numbers
    FROM sys.objects s1
    CROSS JOIN sys.objects s2
ALTER TABLE Numbers ADD CONSTRAINT PK_Numbers PRIMARY KEY CLUSTERED (Number)

一旦设置了 Numbers 表，创建这个拆分函数：

CREATE FUNCTION [dbo].[FN_ListToTable]
(
     @SplitOn  char(1)      --REQUIRED, the character to split the @List string on
    ,@List     varchar(8000)--REQUIRED, the list to split apart
)
RETURNS TABLE
AS
RETURN 
(

    ----------------
    --SINGLE QUERY-- --this will not return empty rows
    ----------------
    SELECT
        ListValue
        FROM (SELECT
                  LTRIM(RTRIM(SUBSTRING(List2, number+1, CHARINDEX(@SplitOn, List2, number+1)-number - 1))) AS ListValue
                  FROM (
                           SELECT @SplitOn + @List + @SplitOn AS List2
                       ) AS dt
                      INNER JOIN Numbers n ON n.Number < LEN(dt.List2)
                  WHERE SUBSTRING(List2, number, 1) = @SplitOn
             ) dt2
        WHERE ListValue IS NOT NULL AND ListValue!=''

);
GO 

您可以随意创建自己的拆分函数，但您仍然需要 Numbers 表才能让我的解决方案发挥作用。

您现在可以轻松地将 CSV 字符串拆分为表格并加入表格：

select * from dbo.FN_ListToTable(',','1,2,3,,,4,5,6777,,,')

输出：

ListValue
-----------------------
1
2
3
4
5
6777

(6 row(s) affected)

现在试试这个：

DECLARE @BaseTable table (RowID int primary key, RowValue varchar(100))
set nocount on
INSERT @BaseTable VALUES ( 1,'The cows came home empty handed')
INSERT @BaseTable VALUES ( 2,'This is my string as a test template to rank')                           -- third
INSERT @BaseTable VALUES ( 3,'pencil pen paperclip eraser')
INSERT @BaseTable VALUES ( 4,'wow')
INSERT @BaseTable VALUES ( 5,'no dice here')
INSERT @BaseTable VALUES ( 6,'This is my string as a test template to rank on even though not exact.') -- second
INSERT @BaseTable VALUES ( 7,'apple banana pear grape lemon orange kiwi strawberry peach watermellon')
INSERT @BaseTable VALUES ( 8,'This is my string as a test template')                                   -- 5th
INSERT @BaseTable VALUES ( 9,'rat cat bat mat sat fat hat pat ')
INSERT @BaseTable VALUES (10,'house home pool roll')
INSERT @BaseTable VALUES (11,'This is my string as a test template to')                                -- 4th
INSERT @BaseTable VALUES (12,'talk wisper yell scream sing hum')
INSERT @BaseTable VALUES (13,'This is my string as a test template to rank on.')                       -- first
INSERT @BaseTable VALUES (14,'aaa bbb ccc ddd eee fff ggg hhh')
INSERT @BaseTable VALUES (15,'three twice three once twice three')
set nocount off

DECLARE @SearchValue varchar(100)
SET @SearchValue='This is my value string as a test template to rank on.'

;WITH SplitBaseTable AS --expand each @BaseTable row into one row per word
(SELECT
     b.RowID, b.RowValue, s.ListValue
     FROM @BaseTable b
         CROSS APPLY  dbo.FN_ListToTable(' ',b.RowValue) AS s
)
, WordMatchCount AS --for each @BaseTable row that has has a word in common withe the search string, get the count of matching words
(SELECT
     s.RowID,COUNT(*) AS CountOfWordMatch
     FROM dbo.FN_ListToTable(' ',@SearchValue) v
         INNER JOIN SplitBaseTable             s ON v.ListValue=s.ListValue
     GROUP BY s.RowID
     HAVING COUNT(*)>0
)
, SearchLen AS --get one row for each possible length of the search string
(
SELECT
    n.Number,SUBSTRING(@SearchValue,1,n.Number) AS PartialSearchValue
    FROM Numbers n
    WHERE n.Number<=LEN(@SearchValue)
)
, MatchLen AS --for each @BaseTable row, get the max starting length that matches the search string
(
 SELECT
     b.RowID,MAX(l.Number) MatchStartLen
     FROM @BaseTable                 b
         LEFT OUTER JOIN SearchLen   l ON LEFT(b.RowValue,l.Number)=l.PartialSearchValue
     GROUP BY b.RowID
)
SELECT --return the final search results
    b.RowValue,w.CountOfWordMatch,m.MatchStartLen
    FROM @BaseTable                     b
        LEFT OUTER JOIN WordMatchCount  w ON b.RowID=w.RowID
        LEFT OUTER JOIN MatchLen        m ON b.RowID=m.RowID
    WHERE w.CountOfWordMatch>0
    ORDER BY w.CountOfWordMatch DESC,m.MatchStartLen DESC,LEN(b.RowValue) DESC,b.RowValue ASC

输出：

RowValue                                                                CountOfWordMatch MatchStartLen
----------------------------------------------------------------------- ---------------- -------------
This is my string as a test template to rank on.                        11               11
This is my string as a test template to rank on even though not exact.  10               11
This is my string as a test template to rank                            10               11
This is my string as a test template to                                 9                11
This is my string as a test template                                    8                11

(5 row(s) affected)

它对字符串开头的单词匹配略有不同，因为它查看匹配字符串开头的字符数。

一旦你得到这个工作，你可以尝试通过为 SplitBaseTable 创建一些静态索引表来优化它。可能在您的 @BaseTable 上使用触发器。

Answer 2

听起来您正在寻找一种匹配算法，如果不使用存储过程，可能很难创建该算法。从过去的经验来看，有edit distance algorithms（如Levenshtein）在确定相似性方面非常有用。这些返回一个数字，有时是字符串之间的一些差异，您可以在其上创建自己的加权方程来给出分数。然后，您可以为分数创建排名或阈值以降低误报/正数。

Answer 3

不久前我有一个类似的问题。我试图回答的问题是在两个不同的列之间匹配了多少单词，并根据匹配单词的最高百分比进行排名。这超出了我的想象，但我从 Martin 那里得到了一个绝妙的答案。

看看他对my question here的回答。

Answer 4

您所有问题的一个答案：使用 sphynx http://sphinxsearch.com 并且不要在 SQL 中解决这个问题。

Sphynx 是开源的，适用于所有数据库和所有操作系统。

这就是 craigslist 所使用的。

这是本文发布时最好的外部全文搜索系统。它将按照您要求的相关性对您的结果进行排序，并且您不需要花哨的 SQL 表或 SQL 过程。试试看。