SELECT * FROM dbo.Catalog where CatalogId=1
CatalogId   CatalogName
----------- -----------
1           Notebooks

SELECT * FROM dbo.Attribute a where a.AttributeId in (select ca.AttributeId from dbo.CatalogAttribute ca where ca.CatalogId=1)
AttributeId AttributeName       AttributeTypeId
----------- ------------------- ---------------
1           CPU                 1
2           RAM, Gb             2
3           Screen Size         3
4           Storage Size, Gb    2
5           Cores               1
6           Screen Technology   1
7           Screen Pixels       1
8           Storage Type        1
9           Graphics            1
10          OS                  1

SELECT top 10 * FROM dbo.Product p where p.CatalogId = 1
ProductId   ProductName                                              CatalogId   BrandId  price     quantity
----------- -------------------------------------------------------- ----------- -------- --------- -----------
1           Ноутбук MSI Titan 18 HX A14VIG-096RU черный              1           13       543999,00    5.000000
2           Ноутбук Razer Blade 18 черный                            1           14       482999,00    5.000000
3           Ноутбук Apple MacBook Pro серебристый                    1           4        454999,00    5.000000
4           Ноутбук ASUS ROG Zephyrus Duo 16 GX650PY-NM040W черный   1           6        447999,00    5.000000
5           Ноутбук Apple MacBook Pro серебристый                    1           4        435999,00    5.000000
6           Ноутбук Apple MacBook Pro черный                         1           4        435999,00    5.000000
7           Ноутбук MSI Raider GE78 HX 14VIG-801RU черный            1           13       433999,00    5.000000
8           Ноутбук AORUS 17X AZF черный                             1           3        419999,00    5.000000
9           Ноутбук Apple MacBook Pro серебристый                    1           4        402999,00    5.000000
10          Ноутбук Apple MacBook Pro черный                         1           4        402999,00    5.000000

SELECT * FROM dbo.AttributeValue av where av.ProductId=1 order by av.AttributeId
AttributeValueId AttributeId ProductId   ValueString                           ValueInt  ValueNumeric
---------------- ----------- ----------- ------------------------------------- --------- -------------
919              1           1           Intel Core i9-14900HX                 NULL      NULL
1531             2           1           NULL                                  32        NULL
1                3           1           NULL                                  NULL      18.000000
2143             4           1           NULL                                  3000      NULL
1225             5           1           8 + 16 x 2.2 GHz + 1.6 GHz            NULL      NULL
613              6           1           mini-LED                              NULL      NULL
307              7           1           3840x2400 (4K)                        NULL      NULL
1837             8           1           SSD                                   NULL      NULL
2449             9           1           GeForce RTX 4090 для ноутбуков 16 Гб  NULL      NULL
2755             10          1           Windows 11 Home                       NULL      NULL

// POST: api/ProductFilter
[HttpPost]
public async Task<ActionResult<IEnumerable<Product>>> FilterProducts(ProductFilter f)
{
    // list of AttributeIds in the filter
    int[] atrIds = f.filters.Keys.ToArray();
    // prepare AttributeTypeIds (required to convert strings to int/numeric)
    Dictionary<int, byte> atrTypes = _context.Attributes
        .Where(a => atrIds.Contains(a.AttributeId))
        .Select(a => new { a.AttributeId, a.AttributeTypeId })
        .ToDictionary(a => a.AttributeId, a => a.AttributeTypeId);
    // base query for Product table. we will expand it later
    var query = from p in _context.Products where p.CatalogId == f.catalogId select p;
    foreach (var filter in f.filters)
    {
        // prepare additional filter for each attribute
        Expression<Func<AttributeValue, bool>>? exprFilters = BuildFilter(filter, atrTypes);
        if (exprFilters == null) continue;
        IQueryable<AttributeValue> v_query = _context.AttributeValues.Where(exprFilters);
        // expand the query by adding additional filters
        query = from p in query
                join v in v_query on p.ProductId equals v.ProductId
                select p;
    }
    return await query.ToListAsync();
}

private static string[] fieldNames = { "", "ValueString", "ValueInt", "ValueNumeric" };
private static Type[] fieldTypes = { typeof(object), typeof(string), typeof(Nullable<int>), typeof(Nullable<decimal>) };
private static Expression<Func<AttributeValue, bool>>? BuildFilter(KeyValuePair<int, string[]> filter, Dictionary<int, byte> atrTypes)
{
    if (filter.Value == null || filter.Value.Length == 0)
        return null;

    byte atrType = atrTypes[filter.Key];
    object? compareTo = null;
    Expression checkValues = null;
    var param = Expression.Parameter(typeof(AttributeValue));
    var fieldToCompare = Expression.Property(param, fieldNames[atrType]);

    foreach (string item in filter.Value)
    {
        compareTo = parseString(atrType, item);
        Expression check = Expression.Equal(
            fieldToCompare,
            Expression.Constant(compareTo, fieldTypes[atrType])
            );
        if (checkValues == null) checkValues = check;
        else checkValues = Expression.OrElse(checkValues, check);
    }
    Expression checkAttributeId = Expression.Equal(
        Expression.Property(param, "AttributeId"),
        Expression.Constant(filter.Key)
        );
    Expression allChecks = Expression.AndAlso(checkAttributeId, checkValues);
    return Expression.Lambda<Func<AttributeValue, bool>>(allChecks, param);
}

version: '3.4'

networks:
  mikesshopnetwork:
    external: false
    name: mikesshopnetwork

volumes:
  sql1data:

services:

  mikesshop.web:
    image: ${DOCKER_REGISTRY-}mikesshopweb
    cpuset: "0"
    networks:
      mikesshopnetwork: {}
    ports:
      - "51387:8080"
    build:
      context: .
      dockerfile: MikesShop.Web/Dockerfile

  sql1:
    image: mcr.microsoft.com/mssql/server:2022-latest
    container_name: sql1
    hostname: sql1
    cpuset: "2"
    environment:
      ACCEPT_EULA: Y
      MSSQL_SA_PASSWORD: 12QWas!@
    volumes:
      - sql1data:/var/opt/mssql
      - c:\src\sql\backup:/var/tmp/backup
    ports:
      - "11433:1433"
    networks:
      mikesshopnetwork: {}