SQL搜索功能问题，LIKE和MATCH

Question

我不得不在其他人的代码中解决一个搜索函数返回太多结果的问题，我注意到它使用了MATCH <，其中LIKE更合适。

我不是SQL太好，我已经改变了所有的比赛对LIKE的..

这显然带来了一个错误，我认为它与针对其即时通讯不知道，但可能是仅做与MATCH一起工作..

这是asp代码中的声明。

strSQL = "" 
     strSQL = "SELECT 'case-studies' AS pagetype, cs.title AS entrytitle, cs.casestudyid AS id, csi.casestudyimageid AS imageid, csi.imagetitle, LIKE (cs.title, cs.content) AGAINST ('" & searchfor & "') AS relevance, LIKE (csi.imagetitle) AGAINST ('" & searchfor & "') AS imagerelevance " 
     strSQL = strSQL & "FROM casestudies AS cs, casestudiesimages AS csi " 
     strSQL = strSQL & "WHERE cs.casestudyid = csi.casestudyid AND cs.modestatus = '1' AND ((LIKE(cs.title, cs.content) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR (LIKE(csi.imagetitle) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR (cs.title like '%" & searchfor & "%') OR (cs.content like '%" & searchfor & "%') OR (csi.imagetitle like '%" & searchfor & "%')) " 
     strSQL = strSQL & "UNION ALL " 
     strSQL = strSQL & "SELECT 'news' AS pagetype, news.title AS entrytitle, news.newsid AS id, newsimages.newsimageid AS imageid, newsimages.imagetitle, LIKE (news.title, news.content) AGAINST ('" & searchfor & "') AS relevance, LIKE (newsimages.imagetitle) AGAINST ('" & searchfor & "') AS imagerelevance " 
     strSQL = strSQL & "FROM news, newsimages " 
     strSQL = strSQL & "WHERE news.newsid = newsimages.newsid AND news.modestatus = '1' AND ((LIKE(news.title, news.content) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR (LIKE(newsimages.imagetitle) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR (news.title like '%" & searchfor & "%') OR (news.content like '%" & searchfor & "%') OR (newsimages.imagetitle like '%" & searchfor & "%')) "   
     strSQL = strSQL & "GROUP BY id " 
     strSQL = strSQL & "ORDER BY relevance DESC, imagerelevance DESC " 

谁能帮助破译这个代码。它需要搜索像像，而不是搜索“他”和获得“帮助”等

感谢

Answer 1

如果您正在使用MyISAM和有对您要搜索的列全文索引，您可以AVO id使用“MATCH .... AGAINST”而不是LIKE进行全表扫描，效率更高。我在MATCH合适的地方替换了“LIKE” - 然后在代码中反对。 SQL的一般规则是，如果要测试的表达式不具有通配符（在这种情况下仅为％），请使用MATCH。

strSQL = "SELECT 'case-studies' AS pagetype, cs.title AS entrytitle, 
      cs.casestudyid AS id, csi.casestudyimageid AS imageid, csi.imagetitle, 
      MATCH (cs.title, cs.content) AGAINST ('" & searchfor & "') AS relevance, 
      MATCH (csi.imagetitle) AGAINST ('" & searchfor & "') AS imagerelevance " 
strSQL = strSQL & "FROM casestudies AS cs, casestudiesimages AS csi " 
strSQL = strSQL & "WHERE cs.casestudyid = csi.casestudyid AND cs.modestatus = '1' AND 
    ((MATCH (cs.title, cs.content) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR 
    (MATCH (csi.imagetitle) AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR 
    (cs.title LIKE '%" & searchfor & "%') OR (cs.content LIKE '%" & 
    searchfor & "%') OR (csi.imagetitle LIKE '%" & searchfor & "%')) " 
strSQL = strSQL & "UNION ALL " 
    strSQL = strSQL & "SELECT 'news' AS pagetype, news.title AS entrytitle, 
     news.newsid AS id, newsimages.newsimageid AS imageid, newsimages.imagetitle, 
     MATCH (news.title, news.content) 
     AGINST ('" & searchfor & "') AS relevance, 
     MATCH (newsimages.imagetitle) 
     AGAINST ('" & searchfor & "') AS imagerelevance " 
    strSQL = strSQL & "FROM news, newsimages " 
    strSQL = strSQL & "WHERE news.newsid = newsimages.newsid AND news.modestatus = '1' 
     AND ((MATCH (news.title, news.content) 
       AGAINST ('" & searchfor & "' IN BOOLEAN MODE)) OR 
     (MATCH (newsimages.imagetitle) AGAINST ('" & searchfor & "' 
     IN BOOLEAN MODE)) OR (news.title LIKE '%" & searchfor & "%') 
     OR (news.content LIKE '%" & searchfor & "%') 
     OR (newsimages.imagetitle LIKE '%" & searchfor & "%')) "   
    strSQL = strSQL & "GROUP BY id " 
    strSQL = strSQL & "ORDER BY relevance DESC, imagerelevance DESC " 

Answer 2

你是说喜欢，但你是不是你比较喜欢的任何东西，一个有效的LIKE语句是

SELECT * 
FROM CUSTOMERS 
WHERE CUSTOMERNAME LIKE '%' + @Param+ '%'