我有个人数据表人，依此类推。有很多列，但有一次感兴趣的是：addressindex，lastname和firstname其中addressindex是一个钻到公寓门口的唯一地址。
因此，如果我“喜欢以下”，则lastname和firstnames中的两个人相同，则他们很可能是重复的。
我需要一种方法来列出这些副本。
tabledata:
personid 1
firstname "Carl"
lastname "Anderson"
addressindex 1
personid 2
firstname "Carl Peter"
lastname "Anderson"
addressindex 1
我知道如果我要在所有列上完全匹配，但是我需要使用模糊匹配来完成（从上面的示例）结果，如下所示：
Row personid addressindex lastname firstname
1 2 1 Anderson Carl Peter
2 1 1 Anderson Carl
.....
有关如何以良好方式解决这个问题的任何提示？
答案 0 :(得分：19)
我发现SQL Server让你做模糊匹配的东西非常笨重。我使用Levenshtein距离算法和一些加权对我自己的CLR函数运气很好。使用该算法，我制作了一个名为GetSimilarityScore的UDF，它接受两个字符串并返回0.0到1.0之间的分数。匹配越接近1.0越好。然后，使用≥1.8左右的阈值进行查询以获得最可能的匹配。像这样：
if object_id('tempdb..#similar') is not null drop table #similar
select a.id, (
select top 1 x.id
from MyTable x
where x.id <> a.id
order by dbo.GetSimilarityScore(a.MyField, x.MyField) desc
) as MostSimilarId
into #similar
from MyTable a
select *, dbo.GetSimilarityScore(a.MyField, c.MyField)
from MyTable a
join #similar b on a.id = b.id
join MyTable c on b.MostSimilarId = c.id
只是不要用非常大的表来做。这是一个缓慢的过程。
这是CLR UDF：
''' <summary>
''' Compute the distance between two strings.
''' </summary>
''' <param name="s1">The first of the two strings.</param>
''' <param name="s2">The second of the two strings.</param>
''' <returns>The Levenshtein cost.</returns>
<Microsoft.SqlServer.Server.SqlFunction()> _
Public Shared Function ComputeLevenstheinDistance(ByVal string1 As SqlString, ByVal string2 As SqlString) As SqlInt32
If string1.IsNull OrElse string2.IsNull Then Return SqlInt32.Null
Dim s1 As String = string1.Value
Dim s2 As String = string2.Value
Dim n As Integer = s1.Length
Dim m As Integer = s2.Length
Dim d As Integer(,) = New Integer(n, m) {}
' Step 1
If n = 0 Then Return m
If m = 0 Then Return n
' Step 2
For i As Integer = 0 To n
d(i, 0) = i
Next
For j As Integer = 0 To m
d(0, j) = j
Next
' Step 3
For i As Integer = 1 To n
'Step 4
For j As Integer = 1 To m
' Step 5
Dim cost As Integer = If((s2(j - 1) = s1(i - 1)), 0, 1)
' Step 6
d(i, j) = Math.Min(Math.Min(d(i - 1, j) + 1, d(i, j - 1) + 1), d(i - 1, j - 1) + cost)
Next
Next
' Step 7
Return d(n, m)
End Function
''' <summary>
''' Returns a score between 0.0-1.0 indicating how closely two strings match. 1.0 is a 100%
''' T-SQL equality match, and the score goes down from there towards 0.0 for less similar strings.
''' </summary>
<Microsoft.SqlServer.Server.SqlFunction()> _
Public Shared Function GetSimilarityScore(string1 As SqlString, string2 As SqlString) As SqlDouble
If string1.IsNull OrElse string2.IsNull Then Return SqlInt32.Null
Dim s1 As String = string1.Value.ToUpper().TrimEnd(" "c)
Dim s2 As String = string2.Value.ToUpper().TrimEnd(" "c)
If s1 = s2 Then Return 1.0F ' At this point, T-SQL would consider them the same, so I will too
Dim flatLevScore As Double = InternalGetSimilarityScore(s1, s2)
Dim letterS1 As String = GetLetterSimilarityString(s1)
Dim letterS2 As String = GetLetterSimilarityString(s2)
Dim letterScore As Double = InternalGetSimilarityScore(letterS1, letterS2)
'Dim wordS1 As String = GetWordSimilarityString(s1)
'Dim wordS2 As String = GetWordSimilarityString(s2)
'Dim wordScore As Double = InternalGetSimilarityScore(wordS1, wordS2)
If flatLevScore = 1.0F AndAlso letterScore = 1.0F Then Return 1.0F
If flatLevScore = 0.0F AndAlso letterScore = 0.0F Then Return 0.0F
' Return weighted result
Return (flatLevScore * 0.2F) + (letterScore * 0.8F)
End Function
Private Shared Function InternalGetSimilarityScore(s1 As String, s2 As String) As Double
Dim dist As SqlInt32 = ComputeLevenstheinDistance(s1, s2)
Dim maxLen As Integer = If(s1.Length > s2.Length, s1.Length, s2.Length)
If maxLen = 0 Then Return 1.0F
Return 1.0F - Convert.ToDouble(dist.Value) / Convert.ToDouble(maxLen)
End Function
''' <summary>
''' Sorts all the alpha numeric characters in the string in alphabetical order
''' and removes everything else.
''' </summary>
Private Shared Function GetLetterSimilarityString(s1 As String) As String
Dim allChars = If(s1, "").ToUpper().ToCharArray()
Array.Sort(allChars)
Dim result As New StringBuilder()
For Each ch As Char In allChars
If Char.IsLetterOrDigit(ch) Then
result.Append(ch)
End If
Next
Return result.ToString()
End Function
''' <summary>
''' Removes all non-alpha numeric characters and then sorts
''' the words in alphabetical order.
''' </summary>
Private Shared Function GetWordSimilarityString(s1 As String) As String
Dim words As New List(Of String)()
Dim curWord As StringBuilder = Nothing
For Each ch As Char In If(s1, "").ToUpper()
If Char.IsLetterOrDigit(ch) Then
If curWord Is Nothing Then
curWord = New StringBuilder()
End If
curWord.Append(ch)
Else
If curWord IsNot Nothing Then
words.Add(curWord.ToString())
curWord = Nothing
End If
End If
Next
If curWord IsNot Nothing Then
words.Add(curWord.ToString())
End If
words.Sort(StringComparer.OrdinalIgnoreCase)
Return String.Join(" ", words.ToArray())
End Function
答案 1 :(得分：16)
除了此处的其他好消息之外，您可能还需要考虑使用Double Metaphone语音算法，该算法通常被认为优于SOUNDEX。
Tim Pfeiffer在他的文章Double Metaphone Sounds Great Convert the C++ Double Metaphone algorithm to T-SQL中详述了SQL中的实现（最初位于SQL Mag＆amp;然后位于SQL Server Pro）。
这将有助于将名称与轻微的拼写错误匹配，例如 Carl 与 Karl 。
更新：实际的可下载代码似乎已消失，但here's an implementation found on a github repo似乎克隆了原始代码
答案 2 :(得分：7)
我会使用SQL Server全文索引，这将允许您进行搜索并返回不仅包含单词而且可能包含拼写错误的内容。
答案 3 :(得分：7)
自首次发布Master Data Services以来，您可以访问比SOUNDEX实现的更高级的模糊逻辑算法。因此，如果您已安装MDS，您将能够在 mdq 架构（MDS数据库）中找到名为 Similarity（）的函数。
有关其工作原理的更多信息：http://blog.hoegaerden.be/2011/02/05/finding-similar-strings-with-fuzzy-logic-functions-built-into-mds/
答案 4 :(得分：4)
我个人使用Jaro-Winkler算法的CLR实现似乎工作得很好 - 它使用超过15个字符的字符串进行了一些操作并且不喜欢匹配电子邮件地址但是其他方面相当不错 - 可以找到完整的实施指南here
如果由于某种原因无法使用CLR功能，也许您可以尝试通过SSIS包运行数据（使用模糊转换查找） - 详细here
答案 5 :(得分：1)
关于重复删除的事情，你的字符串拆分和匹配是很好的第一次切割。如果有可用于减少工作量和/或产生更好结果的数据的已知项目，那么利用它们总是好的。请记住，通常对于重复数据删除而言，不可能完全消除手动工作，尽管您可以通过尽可能多地自动捕获并随后生成“不确定性案例”的报告来更轻松。
关于名称匹配：SOUNDEX对于匹配的质量非常糟糕，特别是对于您要尝试的工作类型而言，因为它会匹配距目标太远的事物。最好使用双metaphone结果和Levenshtein距离的组合来执行名称匹配。通过适当的偏置，这种方法非常有效，并且在对您的知识进行清理后可能会用于第二遍。
您可能还需要考虑使用SSIS包并查看模糊查找和分组转换（http://msdn.microsoft.com/en-us/library/ms345128(SQL.90).aspx).
使用SQL全文搜索（http://msdn.microsoft.com/en-us/library/cc879300.aspx）也是可能的，但可能不适合您的特定问题域。
答案 6 :(得分：1)
分两部分粘贴RedFilter代码，以避免链接腐烂
参考文献：
https://github.com/mb16/geocoderNet/blob/master/build/sql/doubleMetaphone.sql
第1部分：
--WEB LISTING 1: Double Metaphone Script
-------------------------------------
IF OBJECT_ID('fnIsVowel') IS NOT NULL BEGIN DROP FUNCTION fnIsVowel END
GO;
CREATE FUNCTION fnIsVowel( @c char(1) )
RETURNS bit
AS
BEGIN
IF (@c = 'A') OR (@c = 'E') OR (@c = 'I') OR (@c = 'O') OR (@c = 'U') OR (@c = 'Y')
BEGIN
RETURN 1
END
--'ELSE' would worry SQL Server, it wants RETURN last in a scalar function
RETURN 0
END
GO;
-----------------------------------------------
IF OBJECT_ID('fnSlavoGermanic') IS NOT NULL BEGIN DROP FUNCTION fnSlavoGermanic
END
GO;
CREATE FUNCTION fnSlavoGermanic( @Word char(50) )
RETURNS bit
AS
BEGIN
--Catch NULL also...
IF (CHARINDEX('W',@Word) > 0) OR (CHARINDEX('K',@Word) > 0) OR
(CHARINDEX('CZ',@Word) > 0)
--'WITZ' test is in original Lawrence Philips C++ code, but appears to be a subset of the first test for 'W'
-- OR (CHARINDEX('WITZ',@Word) > 0)
BEGIN
RETURN 1
END
--ELSE
RETURN 0
END
GO;
---------------------------------------------------------------------------------------------------------------------------------
----------------------
--Lawrence Philips calls for a length argument, but this has two drawbacks:
--1. All target strings must be of the same length
--2. It presents an opportunity for subtle bugs, ie fnStringAt( 1, 7, 'Search me please', 'Search' ) returns 0 (no matter what is in the searched string)
--So I've eliminated the argument and fnStringAt checks the length of each target as it executes
--DEFAULTS suck with UDFs. Have to specify DEFAULT in caller - why bother?
IF OBJECT_ID('fnStringAtDef') IS NOT NULL BEGIN DROP FUNCTION fnStringAtDef END
GO;
CREATE FUNCTION fnStringAtDef( @Start int, @StringToSearch varchar(50),
@Target1 varchar(50),
@Target2 varchar(50) = NULL,
@Target3 varchar(50) = NULL,
@Target4 varchar(50) = NULL,
@Target5 varchar(50) = NULL,
@Target6 varchar(50) = NULL )
RETURNS bit
AS
BEGIN
IF CHARINDEX(@Target1,@StringToSearch,@Start) > 0 RETURN 1
--2 Styles, test each optional argument for NULL, nesting further tests
--or just take advantage of CHARINDEX behavior with a NULL arg (unless 65 compatibility - code check before CREATE FUNCTION?
--Style 1:
--IF @Target2 IS NOT NULL
--BEGIN
-- IF CHARINDEX(@Target2,@StringToSearch,@Start) > 0 RETURN 1
-- (etc.)
--END
--Style 2:
IF CHARINDEX(@Target2,@StringToSearch,@Start) > 0 RETURN 1
IF CHARINDEX(@Target3,@StringToSearch,@Start) > 0 RETURN 1
IF CHARINDEX(@Target4,@StringToSearch,@Start) > 0 RETURN 1
IF CHARINDEX(@Target5,@StringToSearch,@Start) > 0 RETURN 1
IF CHARINDEX(@Target6,@StringToSearch,@Start) > 0 RETURN 1
RETURN 0
END
GO;
-------------------------------------------------------------------------------------------------
IF OBJECT_ID('fnStringAt') IS NOT NULL BEGIN DROP FUNCTION fnStringAt END
GO;
CREATE FUNCTION fnStringAt( @Start int, @StringToSearch varchar(50), @TargetStrings
varchar(2000) )
RETURNS bit
AS
BEGIN
DECLARE @SingleTarget varchar(50)
DECLARE @CurrentStart int
DECLARE @CurrentLength int
--Eliminate special cases
--Trailing space is needed to check for end of word in some cases, so always append comma
--loop tests should fairly quickly ignore ',,' termination
SET @TargetStrings = @TargetStrings + ','
SET @CurrentStart = 1
--Include terminating comma so spaces don't get truncated
SET @CurrentLength = (CHARINDEX(',',@TargetStrings,@CurrentStart) -
@CurrentStart) + 1
SET @SingleTarget = SUBSTRING(@TargetStrings,@CurrentStart,@CurrentLength)
WHILE LEN(@SingleTarget) > 1
BEGIN
IF SUBSTRING(@StringToSearch,@Start,LEN(@SingleTarget)-1) =
LEFT(@SingleTarget,LEN(@SingleTarget)-1)
BEGIN
RETURN 1
END
SET @CurrentStart = (@CurrentStart + @CurrentLength)
SET @CurrentLength = (CHARINDEX(',',@TargetStrings,@CurrentStart) -
@CurrentStart) + 1
IF NOT @CurrentLength > 1 --getting trailing comma
BEGIN
BREAK
END
SET @SingleTarget =
SUBSTRING(@TargetStrings,@CurrentStart,@CurrentLength)
END
RETURN 0
END
GO;
------------------------------------------------------------------------
IF OBJECT_ID('fnDoubleMetaphoneTable') IS NOT NULL BEGIN DROP FUNCTION
fnDoubleMetaphoneTable END
GO;
CREATE FUNCTION fnDoubleMetaphoneTable( @Word varchar(50) )
RETURNS @DMP TABLE ( Metaphone1 char(4), Metaphone2 char(4) )
AS
BEGIN
DECLARE @MP1 varchar(4), @MP2 varchar(4)
SET @MP1 = ''
SET @MP2 = ''
DECLARE @CurrentPosition int, @WordLength int, @CurrentChar char(1)
SET @CurrentPosition = 1
SET @WordLength = LEN(@Word)
IF @WordLength < 1
BEGIN
RETURN
END
--ensure case insensitivity
SET @Word = UPPER(@Word)
IF dbo.fnStringAt(1, @Word, 'GN,KN,PN,WR,PS') = 1
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
IF 'X' = LEFT(@Word,1)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
SET @CurrentPosition = @CurrentPosition + 1
END
WHILE (4 > LEN(RTRIM(@MP1))) OR (4 > LEN(RTRIM(@MP2)))
BEGIN
IF @CurrentPosition > @WordLength
BEGIN
BREAK
END
SET @CurrentChar = SUBSTRING(@Word,@CurrentPosition,1)
IF @CurrentChar IN('A','E','I','O','U','Y')
BEGIN
IF @CurrentPosition = 1
BEGIN
SET @MP1 = @MP1 + 'A'
SET @MP2 = @MP2 + 'A'
END
SET @CurrentPosition = @CurrentPosition + 1
END
ELSE IF @CurrentChar = 'B'
BEGIN
SET @MP1 = @MP1 + 'P'
SET @MP2 = @MP2 + 'P'
IF 'B' = SUBSTRING(@Word,@CurrentPosition + 1,1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'Ç'
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
SET @CurrentPosition = @CurrentPosition + 1
END
ELSE IF @CurrentChar = 'C'
BEGIN
--various germanic
IF (@CurrentPosition > 2)
AND (dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition-2,1))=0)
AND (dbo.fnStringAt(@CurrentPosition-1,@Word,'ACH') = 1)
AND ((SUBSTRING(@Word,@CurrentPosition+2,1) <> 'I')
AND ((SUBSTRING(@Word,@CurrentPosition+2,1) <> 'E') OR
(dbo.fnStringAt(@CurrentPosition-2,@Word,'BACHER,MACHER')=1)))
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
-- 'caesar'
ELSE IF (@CurrentPosition = 1) AND
(dbo.fnStringAt(@CurrentPosition,@Word,'CAESAR') = 1)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
SET @CurrentPosition = @CurrentPosition + 2
END
-- 'chianti'
ELSE IF dbo.fnStringAt(@CurrentPosition,@Word,'CHIA') = 1
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE IF dbo.fnStringAt(@CurrentPosition,@Word,'CH') = 1
BEGIN
-- Find 'michael'
IF (@CurrentPosition > 1) AND
(dbo.fnStringAt(@CurrentPosition,@Word,'CHAE') = 1)
BEGIN
--First instance of alternate encoding
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'X'
SET @CurrentPosition = @CurrentPosition + 2
END
--greek roots e.g. 'chemistry', 'chorus'
ELSE IF (@CurrentPosition = 1) AND (dbo.fnStringAt(2, @Word,
'HARAC,HARIS,HOR,HYM,HIA,HEM') = 1) AND (dbo.fnStringAt(1,@Word,'CHORE') = 0)
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
--germanic, greek, or otherwise 'ch' for 'kh' sound
ELSE IF ((dbo.fnStringAt(1,@Word,'VAN ,VON ,SCH')=1) OR
(dbo.fnStringAt(@CurrentPosition-
2,@Word,'ORCHES,ARCHIT,ORCHID')=1) OR
(dbo.fnStringAt(@CurrentPosition+2,@Word,'T,S')=1) OR
(((dbo.fnStringAt(@CurrentPosition-1,@Word,'A,O,U,E')=1)
OR
(@CurrentPosition = 1))
AND
(dbo.fnStringAt(@CurrentPosition+2,@Word,'L,R,N,M,B,H,F,V,W, ')=1)))
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
--is this a given?
IF (@CurrentPosition > 1)
BEGIN
IF (dbo.fnStringAt(1,@Word,'MC') = 1)
BEGIN
--eg McHugh
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
ELSE
BEGIN
--Alternate encoding
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'K'
END
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
END
SET @CurrentPosition = @CurrentPosition + 2
END
END
--e.g, 'czerny'
ELSE IF (dbo.fnStringAt(@CurrentPosition,@Word,'CZ')=1) AND
(dbo.fnStringAt((@CurrentPosition - 2),@Word,'WICZ')=0)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'X'
SET @CurrentPosition = @CurrentPosition + 2
END
--e.g., 'focaccia'
ELSE IF(dbo.fnStringAt((@CurrentPosition + 1),@Word,'CIA')=1)
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
SET @CurrentPosition = @CurrentPosition + 3
END
--double 'C', but not if e.g. 'McClellan'
ELSE IF(dbo.fnStringAt(@CurrentPosition,@Word,'CC')=1) AND NOT
((@CurrentPosition = 2) AND (LEFT(@Word,1) = 'M'))
--'bellocchio' but not 'bacchus'
IF (dbo.fnStringAt((@CurrentPosition + 2),@Word,'I,E,H')=1) AND
(dbo.fnStringAt((@CurrentPosition + 2),@Word,'HU')=0)
BEGIN
--'accident', 'accede' 'succeed'
IF (((@CurrentPosition = 2) AND
(SUBSTRING(@Word,@CurrentPosition - 1,1) = 'A'))
OR (dbo.fnStringAt((@CurrentPosition -
1),@Word,'UCCEE,UCCES')=1))
BEGIN
SET @MP1 = @MP1 + 'KS'
SET @MP2 = @MP2 + 'KS'
END
--'bacci', 'bertucci', other italian
ELSE
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
END
SET @CurrentPosition = @CurrentPosition + 3
END
--Pierce's rule
ELSE
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE IF (dbo.fnStringAt(@CurrentPosition,@Word,'CK,CG,CQ')=1)
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE IF (dbo.fnStringAt(@CurrentPosition,@Word,'CI,CE,CY')=1)
BEGIN
--italian vs. english
IF (dbo.fnStringAt(@CurrentPosition,@Word,'CIO,CIE,CIA')=1)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'X'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
END
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
--name sent in 'mac caffrey', 'mac gregor
IF (dbo.fnStringAt((@CurrentPosition + 1),@Word,' C, Q, G')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 3
END
ELSE
BEGIN
IF (dbo.fnStringAt((@CurrentPosition + 1),@Word,'C,K,Q')=1)
AND (dbo.fnStringAt((@CurrentPosition + 1), 2, 'CE,CI')=0)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
END
END
ELSE IF @CurrentChar = 'D'
BEGIN
IF (dbo.fnStringAt(@CurrentPosition, @Word, 'DG')=1)
BEGIN
IF (dbo.fnStringAt((@CurrentPosition + 2),@Word,'I,E,Y')=1)
BEGIN
--e.g. 'edge'
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'J'
SET @CurrentPosition = @CurrentPosition + 3
END
ELSE
BEGIN
--e.g. 'edgar'
SET @MP1 = @MP1 + 'TK'
SET @MP2 = @MP2 + 'TK'
SET @CurrentPosition = @CurrentPosition + 2
END
END
ELSE IF (dbo.fnStringAt(@CurrentPosition,@Word,'DT,DD')=1)
BEGIN
SET @MP1 = @MP1 + 'T'
SET @MP2 = @MP2 + 'T'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'T'
SET @MP2 = @MP2 + 'T'
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'F'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'F')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'F'
SET @MP2 = @MP2 + 'F'
END
ELSE IF @CurrentChar = 'G'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'H')
BEGIN
IF (@CurrentPosition > 1) AND
(dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition - 1,1)) = 0)
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
SET @CurrentPosition = @CurrentPosition + 2
END
--'ghislane', ghiradelli
ELSE IF (@CurrentPosition = 1)
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 2,1) = 'I')
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'J'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
SET @CurrentPosition = @CurrentPosition + 2
END
--Parker's rule (with some further refinements) - e.g., 'hugh'
ELSE IF (((@CurrentPosition > 2) AND (dbo.fnStringAt((@CurrentPosition
- 2),@Word,'B,H,D')=1) )
--e.g., 'bough'
OR ((@CurrentPosition > 3) AND (dbo.fnStringAt((@CurrentPosition
- 3),@Word,'B,H,D')=1) )
--e.g., 'broughton'
OR ((@CurrentPosition > 4) AND (dbo.fnStringAt((@CurrentPosition
- 4),@Word,'B,H')=1) ) )
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
--e.g., 'laugh', 'McLaughlin', 'cough', 'gough', 'rough', 'tough'
IF ((@CurrentPosition > 3)
AND (SUBSTRING(@Word,@CurrentPosition - 1,1) = 'U')
AND (dbo.fnStringAt((@CurrentPosition -
3),@Word,'C,G,L,R,T')=1) )
BEGIN
SET @MP1 = @MP1 + 'F'
SET @MP2 = @MP2 + 'F'
END
ELSE
BEGIN
IF ((@CurrentPosition > 1) AND
SUBSTRING(@Word,@CurrentPosition - 1,1) <> 'I')
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
END
SET @CurrentPosition = @CurrentPosition + 2
END
END
ELSE IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'N')
BEGIN
IF ((@CurrentPosition = 2) AND (dbo.fnIsVowel(LEFT(@Word,1))=1) AND
(dbo.fnSlavoGermanic(@Word)=0))
BEGIN
SET @MP1 = @MP1 + 'KN'
SET @MP2 = @MP2 + 'N'
END
ELSE
BEGIN
--not e.g. 'cagney'
IF ((dbo.fnStringAt((@CurrentPosition + 2),@Word,'EY')=0)
AND (SUBSTRING(@Word,@CurrentPosition + 1,1) <>
'Y') AND (dbo.fnSlavoGermanic(@Word)=0))
答案 7 :(得分：1)
代码的第二部分对于Redfilter中的链接的答案：
参考文献：
https://github.com/mb16/geocoderNet/blob/master/build/sql/doubleMetaphone.sql
BEGIN
SET @MP1 = @MP1 + 'N'
SET @MP2 = @MP2 + 'KN'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'KN'
SET @MP2 = @MP2 + 'KN'
END
END
SET @CurrentPosition = @CurrentPosition + 2
END
--'tagliaro'
ELSE IF (dbo.fnStringAt((@CurrentPosition + 1),@Word,'LI')=1) AND
(dbo.fnSlavoGermanic(@Word)=0)
BEGIN
SET @MP1 = @MP1 + 'KL'
SET @MP2 = @MP2 + 'L'
SET @CurrentPosition = @CurrentPosition + 2
END
-- -ges-,-gep-,-gel-, -gie- at beginning
-- This call to fnStringAt() is the 'worst case' in number of values passed. A UDF that used DEFAULT values instead of
-- a multi-valued argument would require ten DEFAULT arguments for EP, EB, EL, etc. (assuming the first was not defined with a DEFAULT).
ELSE IF ((@CurrentPosition = 1)
AND ((SUBSTRING(@Word,@CurrentPosition + 1,1) = 'Y')
OR (dbo.fnStringAt((@CurrentPosition +
1),@Word,'ES,EP,EB,EL,EY,IB,IL,IN,IE,EI,ER')=1)) )
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'J'
SET @CurrentPosition = @CurrentPosition + 2
END
-- -ger-, -gy-
ELSE IF (((dbo.fnStringAt((@CurrentPosition + 1), @Word, 'ER')=1) OR
(SUBSTRING(@Word,@CurrentPosition + 1,1) = 'Y'))
AND (dbo.fnStringAt(1, @Word, 'DANGER,RANGER,MANGER')=0)
AND (dbo.fnStringAt((@CurrentPosition - 1), @Word,
'E,I,RGY,OGY')=0) )
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'J'
SET @CurrentPosition = @CurrentPosition + 2
END
-- italian e.g, 'biaggi'
ELSE IF (dbo.fnStringAt((@CurrentPosition + 1),@Word,'E,I,Y')=1) OR
(dbo.fnStringAt((@CurrentPosition - 1),@Word,'AGGI,OGGI')=1)
BEGIN
--obvious germanic
IF ((dbo.fnStringAt(1,@Word,'VAN ,VON ,SCH')=1)
OR (dbo.fnStringAt((@CurrentPosition + 1),@Word,'ET')=1))
BEGIN
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
ELSE
BEGIN
--always soft if french ending
IF (dbo.fnStringAt((@CurrentPosition + 1),@Word,'IER ')=1)
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'J'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'K'
END
END
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'G')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
END
ELSE IF @CurrentChar = 'H'
BEGIN
--only keep if first & before vowel or btw. 2 vowels
IF (((@CurrentPosition = 1) OR
(dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition - 1,1))=1))
AND (dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition + 1,1))=1))
BEGIN
SET @MP1 = @MP1 + 'H'
SET @MP2 = @MP2 + 'H'
SET @CurrentPosition = @CurrentPosition + 2
END
--also takes care of 'HH'
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'J'
BEGIN
--obvious spanish, 'jose', 'san jacinto'
IF (dbo.fnStringAt(@CurrentPosition,@Word,'JOSE')=1) OR
(dbo.fnStringAt(1,@Word,'SAN ')=1)
BEGIN
IF (((@CurrentPosition = 1) AND (SUBSTRING(@Word,@CurrentPosition
+ 4,1) = ' ')) OR (dbo.fnStringAt(1,@Word,'SAN ')=1) )
BEGIN
SET @MP1 = @MP1 + 'H'
SET @MP2 = @MP2 + 'H'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'H'
END
SET @CurrentPosition = @CurrentPosition + 1
END
ELSE IF ((@CurrentPosition = 1) AND
(dbo.fnStringAt(@CurrentPosition,@Word,'JOSE')=0))
BEGIN
SET @MP1 = @MP1 + 'J'
--Yankelovich/Jankelowicz
SET @MP2 = @MP2 + 'A'
--it could happen!
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'J')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE
BEGIN
--spanish pron. of e.g. 'bajador'
IF( (dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition - 1,1))=1)
AND (dbo.fnSlavoGermanic(@Word)=0)
AND ((SUBSTRING(@Word,@CurrentPosition + 1,1) = 'A') OR
(SUBSTRING(@Word,@CurrentPosition + 1,1) = 'O')))
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'H'
END
ELSE
BEGIN
IF (@CurrentPosition = @WordLength)
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + ''
END
ELSE
BEGIN
IF ((dbo.fnStringAt((@CurrentPosition + 1), @Word,
'L,T,K,S,N,M,B,Z')=0)
AND (dbo.fnStringAt((@CurrentPosition - 1), @Word,
'S,K,L')=0))
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'J'
END
END
END
--it could happen!
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'J')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
END
ELSE IF @CurrentChar = 'K'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'K')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
ELSE IF @CurrentChar = 'L'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'L')
BEGIN
--spanish e.g. 'cabrillo', 'gallegos'
IF (((@CurrentPosition = (@WordLength - 3))
AND (dbo.fnStringAt((@CurrentPosition -
1),@Word,'ILLO,ILLA,ALLE')=1))
OR (((dbo.fnStringAt((@WordLength - 1),@Word,'AS,OS')=1)
OR (dbo.fnStringAt(@WordLength,@Word,'A,O')=1))
AND (dbo.fnStringAt((@CurrentPosition -
1),@Word,'ALLE')=1)) )
BEGIN
SET @MP1 = @MP1 + 'L'
SET @MP2 = @MP2 + ''
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
SET @MP1 = @MP1 + 'L'
SET @MP2 = @MP2 + 'L'
END
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
SET @MP1 = @MP1 + 'L'
SET @MP2 = @MP2 + 'L'
END
END
ELSE IF @CurrentChar = 'M'
BEGIN
--'dumb','thumb'
IF (((dbo.fnStringAt((@CurrentPosition - 1), @Word,'UMB')=1)
AND (((@CurrentPosition + 1) = @WordLength) OR
(dbo.fnStringAt((@CurrentPosition + 2),@Word,'ER')=1)))
OR (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'M') )
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'M'
SET @MP2 = @MP2 + 'M'
END
ELSE IF @CurrentChar = 'N'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'N')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'N'
SET @MP2 = @MP2 + 'N'
END
ELSE IF @CurrentChar = 'Ñ'
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
SET @MP1 = @MP1 + 'N'
SET @MP2 = @MP2 + 'N'
END
ELSE IF @CurrentChar = 'P'
BEGIN
--What about Michelle Pfeiffer, star of Grease 2? Price-Pfister?, Pfizer?
--Don't just look for an 'F' next, what about 'topflight', helpful, campfire, leapfrog, stepfather
--Sorry, Mark Knopfler, I don't know how to help you
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'H')
OR ((@CurrentPosition = 1) AND
(SUBSTRING(@Word,@CurrentPosition + 1,1) = 'F') AND
(dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition+2,1))=1))
BEGIN
SET @MP1 = @MP1 + 'F'
SET @MP2 = @MP2 + 'F'
SET @CurrentPosition = @CurrentPosition + 2
END
--also account for "campbell", "raspberry"
ELSE
BEGIN
IF (dbo.fnStringAt((@CurrentPosition + 1),@Word, 'P,B')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'P'
SET @MP2 = @MP2 + 'P'
END
END
ELSE IF @CurrentChar = 'Q'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'Q')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'K'
SET @MP2 = @MP2 + 'K'
END
ELSE IF @CurrentChar = 'R'
BEGIN
--QQ: Will SQL short circuit eval? Otherwise, I could try to read before string begins here...
--french e.g. 'rogier', but exclude 'hochmeier'
IF ((@CurrentPosition = @WordLength)
AND (dbo.fnSlavoGermanic(@Word)=0)
AND (dbo.fnStringAt((@CurrentPosition - 2), @Word, 'IE')=1)
AND (dbo.fnStringAt((@CurrentPosition - 4), @Word,
'ME,MA')=0))
BEGIN
SET @MP1 = @MP1 + ''
SET @MP2 = @MP2 + 'R'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'R'
SET @MP2 = @MP2 + 'R'
END
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'R')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'S'
BEGIN
--special cases 'island', 'isle', 'carlisle', 'carlysle'
IF (dbo.fnStringAt((@CurrentPosition - 1), @Word, 'ISL,YSL')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
--special case 'sugar-'
ELSE IF ((@CurrentPosition = 1) AND (dbo.fnStringAt(@CurrentPosition,
@Word, 'SUGAR')=1))
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'S'
SET @CurrentPosition = @CurrentPosition + 1
END
ELSE IF (dbo.fnStringAt(@CurrentPosition, @Word, 'SH')=1)
BEGIN
--germanic
IF (dbo.fnStringAt((@CurrentPosition + 1), @Word,
'HEIM,HOEK,HOLM,HOLZ')=1)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
END
SET @CurrentPosition = @CurrentPosition + 2
END
--italian & armenian
ELSE IF (dbo.fnStringAt(@CurrentPosition, @Word, 'SIO,SIA')=1) OR
(dbo.fnStringAt(@CurrentPosition, @Word, 'SIAN')=1)
BEGIN
IF (dbo.fnSlavoGermanic(@Word)=0)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'X'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
END
SET @CurrentPosition = @CurrentPosition + 3
END
--german & anglicisations, e.g. 'smith' match 'schmidt', 'snider' match 'schneider'
--also, -sz- in slavic language altho in hungarian it is pronounced 's'
ELSE IF (((@CurrentPosition = 1)
AND (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'M,N,L,W')=1))
OR (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'Z')=1))
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'X'
IF (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'Z')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF (dbo.fnStringAt(@CurrentPosition, @Word, 'SC')=1)
BEGIN
--Schlesinger's rule
IF (SUBSTRING(@Word,@CurrentPosition + 2,1) = 'H')
BEGIN
--dutch origin, e.g. 'school', 'schooner'
IF (dbo.fnStringAt((@CurrentPosition + 3), @Word,
'OO,ER,EN,UY,ED,EM')=1)
BEGIN
--'schermerhorn', 'schenker'
IF (dbo.fnStringAt((@CurrentPosition + 3), @Word, 'ER,EN')=1)
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'SK'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'SK'
SET @MP2 = @MP2 + 'SK'
END
SET @CurrentPosition = @CurrentPosition + 3
END
ELSE
BEGIN
IF ((@CurrentPosition = 1) AND
(dbo.fnIsVowel(SUBSTRING(@Word,3,1))=0) AND (SUBSTRING(@Word,3,1) <> 'W'))
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'S'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
END
SET @CurrentPosition = @CurrentPosition + 3
END
END
ELSE IF (dbo.fnStringAt((@CurrentPosition + 2), @Word, 'I,E,Y')=1)
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
SET @CurrentPosition = @CurrentPosition + 3
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'SK'
SET @MP2 = @MP2 + 'SK'
SET @CurrentPosition = @CurrentPosition + 3
END
END
ELSE
BEGIN
--french e.g. 'resnais', 'artois'
IF ((@CurrentPosition = @WordLength) AND
(dbo.fnStringAt((@CurrentPosition - 2), @Word, 'AI,OI')=1))
BEGIN
SET @MP1 = @MP1 + ''
SET @MP2 = @MP2 + 'S'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
END
IF (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'S,Z')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
END
ELSE IF @CurrentChar = 'T'
BEGIN
IF (dbo.fnStringAt(@CurrentPosition, @Word, 'TION,TIA,TCH')=1)
BEGIN
SET @MP1 = @MP1 + 'X'
SET @MP2 = @MP2 + 'X'
SET @CurrentPosition = @CurrentPosition + 3
END
ELSE IF (dbo.fnStringAt(@CurrentPosition, @Word, 'TH,TTH')=1)
BEGIN
--special case 'thomas', 'thames' or germanic
IF (dbo.fnStringAt((@CurrentPosition + 2), @Word, 'OM,AM')=1)
OR (dbo.fnStringAt(1, @Word, 'VAN ,VON ,SCH')=1)
BEGIN
SET @MP1 = @MP1 + 'T'
SET @MP2 = @MP2 + 'T'
END
ELSE
BEGIN
SET @MP1 = @MP1 + '0'
SET @MP2 = @MP2 + 'T'
END
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
IF (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'T,D')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'T'
SET @MP2 = @MP2 + 'T'
END
END
ELSE IF @CurrentChar = 'V'
BEGIN
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'V')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
SET @MP1 = @MP1 + 'F'
SET @MP2 = @MP2 + 'F'
END
ELSE IF @CurrentChar = 'W'
BEGIN
--can also be in middle of word
IF (dbo.fnStringAt(@CurrentPosition, @Word, 'WR')=1)
BEGIN
SET @MP1 = @MP1 + 'R'
SET @MP2 = @MP2 + 'R'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE IF ((@CurrentPosition = 1)
AND ((dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition + 1,1))=1)
OR (dbo.fnStringAt(@CurrentPosition, @Word, 'WH')=1)))
BEGIN
--Wasserman should match Vasserman
IF (dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition + 1,1))=1)
BEGIN
SET @MP1 = @MP1 + 'A'
SET @MP2 = @MP2 + 'F'
END
ELSE
BEGIN
--need Uomo to match Womo
SET @MP1 = @MP1 + 'A'
SET @MP2 = @MP2 + 'A'
END
SET @CurrentPosition = @CurrentPosition + 1
END
--Arnow should match Arnoff
ELSE IF (((@CurrentPosition = @WordLength) AND
(dbo.fnIsVowel(SUBSTRING(@Word,@CurrentPosition - 1,1))=1))
OR (dbo.fnStringAt((@CurrentPosition - 1), @Word,
'EWSKI,EWSKY,OWSKI,OWSKY')=1)
OR (dbo.fnStringAt(1, @Word, 'SCH')=1))
BEGIN
SET @MP1 = @MP1 + ''
SET @MP2 = @MP2 + 'F'
SET @CurrentPosition = @CurrentPosition + 1
END
--polish e.g. 'filipowicz'
ELSE IF (dbo.fnStringAt(@CurrentPosition, @Word, 'WICZ,WITZ')=1)
BEGIN
SET @MP1 = @MP1 + 'TS'
SET @MP2 = @MP2 + 'FX'
SET @CurrentPosition = @CurrentPosition + 4
END
-- skip it
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'X'
BEGIN
--french e.g. breaux
IF (NOT((@CurrentPosition = @WordLength)
AND ((dbo.fnStringAt((@CurrentPosition - 3), @Word, 'IAU,EAU')=1)
OR (dbo.fnStringAt((@CurrentPosition - 2), @Word,
'AU,OU')=1))) )
BEGIN
SET @MP1 = @MP1 + 'KS'
SET @MP2 = @MP2 + 'KS'
END
IF (dbo.fnStringAt((@CurrentPosition + 1), @Word, 'C,X')=1)
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
ELSE IF @CurrentChar = 'Z'
BEGIN
--chinese pinyin e.g. 'zhao'
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'H')
BEGIN
SET @MP1 = @MP1 + 'J'
SET @MP2 = @MP2 + 'J'
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
IF ((dbo.fnStringAt((@CurrentPosition + 1), @Word, 'ZO,ZI,ZA')=1)
OR ((dbo.fnSlavoGermanic(@Word)=1) AND ((@CurrentPosition >
1) AND SUBSTRING(@Word,@CurrentPosition - 1,1) <> 'T')))
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'TS'
END
ELSE
BEGIN
SET @MP1 = @MP1 + 'S'
SET @MP2 = @MP2 + 'S'
END
IF (SUBSTRING(@Word,@CurrentPosition + 1,1) = 'Z')
BEGIN
SET @CurrentPosition = @CurrentPosition + 2
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
END
ELSE
BEGIN
SET @CurrentPosition = @CurrentPosition + 1
END
END
--only give back 4 char metaphone
IF (LEN(@MP1) > 4)
BEGIN
SET @MP1 = LEFT(@MP1, 4)
END
IF (LEN(@MP2) > 4)
BEGIN
SET @MP2 = LEFT(@MP2, 4)
END
IF @MP2 = @MP1
BEGIN
SET @MP2 = ''
END
INSERT @DMP(Metaphone1,Metaphone2) VALUES( @MP1, @MP2 )
RETURN
END
GO;
------------------------------------------------------------------------
IF OBJECT_ID('fnDoubleMetaphoneScalar') IS NOT NULL BEGIN DROP FUNCTION
fnDoubleMetaphoneScalar END
GO;
CREATE FUNCTION fnDoubleMetaphoneScalar( @MetaphoneType int, @Word varchar(50) )
RETURNS char(4)
AS
BEGIN
RETURN (SELECT CASE @MetaphoneType WHEN 1 THEN Metaphone1
WHEN 2 THEN Metaphone2 END FROM fnDoubleMetaphoneTable( @Word ))
END
答案 8 :(得分：0)
您可以使用SQL Server中的SOUNDEX和相关的DIFFERENCE函数来查找类似的名称。 MSDN上的参考是here。
答案 9 :(得分：0)
这样做
create table person(
personid int identity(1,1) primary key,
firstname varchar(20),
lastname varchar(20),
addressindex int,
sound varchar(10)
)
以及稍后创建触发器
create trigger trigoninsert for dbo.person
on insert
as
declare @personid int;
select @personid=personid from inserted;
update person
set sound=soundex(firstname) where personid=@personid;
现在我可以做的是我可以创建一个看起来像这样的程序
create procedure getfuzzi(@personid int)
as
declare @sound varchar(10);
set @sound=(select sound from person where personid=@personid;
select personid,firstname,lastname,addressindex from person
where sound=@sound
这将返回所有与特定personid
提供的名称几乎匹配的名称