在Lucene中查询 [英] Query in Lucene

问题描述

表testtable的结构是

1. id int主键




2. productid int




3. attributeid int




4. 值varchar（250）
   

其中productid是产品的唯一标识，
attributeid是唯一标识产品的属性例如尺寸，质量，身高，颜色
和'价值'是属性值

我必须过滤结果。我通过这个查询来达到要求。
但是我无法在查询中完成它。

 从dbo.testtable中选择a。* a 
其中a.attributeId = 10和a。[Value] = 'Romance'
和productId in 
（
）从
中选择productId 
 dbo.testtable其中attributeId = 7和[Value] ='印地语'
） 
  

需要帮助来构建这个查询..

解决方案

我认为你必须分两步来做：

第1步：提取产品id

  BooleanQuery query = new BooleanQuery（）; 
 
 query.add（新的TermQuery（attributeId，7），BooleanClause.Occur.MUST）; 
 query.add（新的TermQuery（value，hindi），BooleanClause.Occur.MUST）; 
 TopDocs docs = searcher.search（query，null，searchLimit）; 
  

然后您需要从文档中提取productId

第二步：运行查询

  BooleanQuery query = new BooleanQuery（）; 
 
 query.add（新的TermQuery（attributeId，10），BooleanClause.Occur.MUST）; 
 query.add（新的TermQuery（value，Romance），BooleanClause.Occur.MUST）; 
 
 //建立IN子句
 BooleanQuery pidQuery = new BooleanQuery（）; （long productId：productIds）{
 pidQuery.add（new TermQuery（productId，productId），BooleanClause.Occur.SHOULD）; 
} 
 query.add（pidQuery，BooleanClause.Occur.MUST）; 
 TopDocs docs = searcher.search（query，null，searchLimit）; 
  

The structure of the table "testtable" is

1. id int primary key

2. productid int

3. attributeid int

4. value varchar(250)

where productid is the unique id of a product, attributeid is the unique id of attribute of a product e.g. size, quality,height, color and 'value' is the value for the attribute

i have to filter a result. I achieve the requirement by this query. But i am not able to make it in a query.

select a.* from dbo.testtable a
where a.attributeId=10 and a.[Value]='Romance'
and productId in
(
    select productId
    from
    dbo.testtable where attributeId =7 and [Value]='Hindi'
)

Need help to build this query..

解决方案

I think you have to do this in two steps:

Step 1: extract product ids

BooleanQuery query = new BooleanQuery();

query.add(new TermQuery("attributeId", 7), BooleanClause.Occur.MUST); 
query.add(new TermQuery("value", "hindi"), BooleanClause.Occur.MUST); 
TopDocs docs = searcher.search(query, null, searchLimit);

You then need to extract the productId from the docs

Step 2: run query

BooleanQuery query = new BooleanQuery();

query.add(new TermQuery("attributeId", 10), BooleanClause.Occur.MUST); 
query.add(new TermQuery("value", "Romance"), BooleanClause.Occur.MUST); 

// build "IN" clause
BooleanQuery pidQuery = new BooleanQuery();
for( long productId : productIds ){
    pidQuery.add(new TermQuery("productId", productId), BooleanClause.Occur.SHOULD); 
}
query.add(pidQuery, BooleanClause.Occur.MUST); 
TopDocs docs = searcher.search(query, null, searchLimit);

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