RavenDB: how to transform a query into a lucene query?

问题

I have the following code:

public class Continent
{
    public string Name { get; set; }
    public List<Country> Countries{ get; set; }
}

public class Countries
{
   public string Name { get; set; }
   public List<Province> Provinces{ get; set; }
}

public class Province
{
    public string Name { get; set; }
    public List<Province> Cities { get; set; }
}

public class City
{
    public string Name { get; set; }
    public string Address   { get; set; }
}

I want to transform the following query into a lucene query(e.g., Where, Any), so that I get the continents where both Aloma and Hemane are within the same province (and not in distinct provinces) with the respective addresses 123 and 435:

 var queryResults = from continent in session
                              .Advanced.DocumentQuery<Continent>()
                               from country in continent.Countries
                               from prov in country.Provinces
                               let cities_ = prov.Cities
                               let fi = cities_.Where(fp => fp.Name == "Aloma" && fp.Address == "123").FirstOrDefault()
                               let fj = cities_.Where(fk => fk.Name == "Hemane" && fk.Address == "435").FirstOrDefault()
                               where fi != null && fj != null
                               select continent;

I originally tried the following, but it returns results when Aloma and Hemane are in the same province (what I want), but also when Aloma and Hemane are in distinct provinces (what I don't want):

var queryResultsLucene = session.Advanced.DocumentQuery<Continent>()
                                 .Where("Countries,Provinces,Cities,Name:Aloma")
                                 .AndAlso()
                                 .Where("Countries,Provinces,Cities,Address:123")
                                 .Intersect()
                                  .Where("Countries,Provinces,Cities,Name:Hemane")
                                 .AndAlso()
                                 .Where("Countries,Provinces,Cities,Address:435")
                                 .OfType<Topic>()
                                 .ToList();

Can you please help me? Thanks in advance

回答1:

I would use the Lucene query from my response on RavenDB: how to transform a session.Query into a session.Advanced.DocumentQuery? . I wouldn't use this with a large number of cities though.

 var continentsToFindByCity = new List<City>(){new City{Name = "Aloma", Address = "123"}, new City{Name = "Hemane", Address = "435"}};
 var results = new List<Continent>();


    foreach(var city in continentsToFindByCity)
    {
        var tempResults = session.Advanced.DocumentQuery<Continent>().Where(
            string.Format("Countries,Provinces,Cities,Name: {0} AND Countries,Provinces,Cities,Address: {1}", city.Name, city.Address)).ToList();

        if(tempResults.Count > 0)
            results.AddRange(tempResults);
    }

回答2:

You can use the following query:

var queryResults = session.Advanced.DocumentQuery<Continent>()
                    .OpenSubClause()
                        .WhereEquals("Countries,Provinces,Cities.Name", "Aloma")
                        .AndAlso()
                        .WhereEquals("Countries,Provinces,Cities.Address", "123")
                    .CloseSubClause()
                    .AndAlso()
                    .OpenSubClause()
                        .WhereEquals("Countries,Provinces,Cities.Name", "Hemane")
                        .AndAlso()
                        .WhereEquals("Countries,Provinces,Cities.Address", "Hemane")
                    .CloseSubClause()
                    .ToList();

来源：https://stackoverflow.com/questions/34444396/ravendb-how-to-transform-a-query-into-a-lucene-query

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nested

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hierarchy