将 RediSearch 与 NRediSearch (C#) 一起使用，如何在两个数字字段上应用 OR 子句，例如 i.CountyId == id || i.CityId == id

Question

I am developing a .Net Core web app with RediSearch. Previously I have used in-app memory cache, but I have to change it to distributed cache. The issue is, the web app has very complex searches which must be handled from cache. I though I just move the cache to Redis and must filter in Linq will stay the same just as with in-app memory cache, but if you have 500K+ entries in Redis, using a docker image on the same host took around 4 sec just to load these entries into a variable so this is not an option.

I have now implemented RediSearch with NRediSearch which seem to handle the load pretty well. The issue I have now, I have a search with multiple location fields.

Example

class Item{
    public int Id {get;set;}
    public int CountyId {get;set;}
    public int CityId {get;set;}
}
class Location{
    public int LocationId {get;set;}
    public bool IsCounty {get;set;}
}

I need to translate the following Linq command into RediSearch

public List<Item> Search(List<Location> location){
    var result = items.Where(i => location.Any(l => l.IsCounty && l.Id == i.CountyId) || location.Any(l => !l.IsCounty && i.CityId == l.Id))
}

I have read the RediSearch documentation, but have not found any answer yet. I have to do this in one search because of sorting.

Answer 1

I have found he answer.

FT.SEARCH idx "@title|body:(hello world) @url|image:mydomain"

Probably if NRediSearch can handle this or operator within a new query, if not, must be implemented straight through it's client

Answer 2

you can use my library i build over nredisearch. but it works for simple linq queries. its not work on nested objects. I will be glad if you contribute to its development.

if we talk about your example you have to duplicate your data for each location like this:

class Item {

    public int Id {get;set;}
    public int CountyId {get;set;}
    public int CityId {get;set;}
    public int LocationId {get;set;}
    public bool IsCounty {get;set;}
}

and you can search this daha with my library.

RedisworkCore

PackageManager:

Install-Package RedisworkCore

Dotnet CLI:

dotnet add package RedisworkCore

and you can create context like entityframework:

public class Person
{
    [RedisKey(0)]
    public int Id { get; set; }
    public string Name { get; set; }
    public string Lastname { get; set; }
}

public class SimpleContext : RedisContext
{
    public Rediset<Person> Persons { get; set; }
    public SimpleContext(RedisContextOptions options) : base(options) { }
}

then you can use Find, Where, Any, All, SortBy, SortByDescending, Skip, Take similar LINQ.

static async Task Main(string[] args)
{

  RedisContextOptions options = new RedisContextOptions
  {
    HostAndPort = "localhost:6379"
  };

  using (var context = new SimpleContext(options))
  {
    var person = new Person
    {
      Id = 26,
      Name = "Emre",
      Lastname = "Hızlı"
    };
    context.Persons.Add(person);
    await context.SaveChangesAsync();
  }

  using (var context = new SimpleContext(options))
  {
    Person person = await context.Persons.Find(26);
    List<Person> persons = await context.Persons.Where(x => x.Id > 0).ToListAsync();
  }
  
}

Notes:

• You should save your data with redisworkcore otherwise it won't work.
• Performance tests were not conducted. It may work better if I can get support as open source.