Construction of a parent/child relationship using a single result set exception #524
Description
Describe the bug
I have a ASP.NET Core API. When I'm trying to get parent/child results from single dataset from SQL Server stored procedure, I got System.NullReferenceException: "Object reference not set to an instance of an object." error.
Steps to reproduce
- Dataset
Id ParentId Index Name
1 NULL 1 [{"Key":"en","Value":"Priority 1"}]
2 1 1 [{"Key":"en","Value":"Priority 1 Subpriority 1"}]
3 1 2 [{"Key":"en","Value":"Priority 1 Subpriority 2"}]
4 1 3 [{"Key":"en","Value":"Priority 1 Subpriority 3"}]
7 1 4 [{"Key":"en","Value":"Priority 1 Subpriority 4"}]
8 1 5 [{"Key":"en","Value":"Priority 1 Subpriority 5"}]
9 NULL 2 [{"Key":"en","Value":"Priority 2"}]
11 9 1 [{"Key":"en","Value":"Priority 2 Subpriority 1"}]
12 9 2 [{"Key":"en","Value":"Priority 2 Subpriority 2"}]
- Model
public class PriorityModel
{
[RecordId]
public int Id { get; set; }
[ParentRecordId]
public int? ParentId { get; set; }
public int IndexNumber { get; set; }
[Column(SerializationMode = SerializationMode.Json)]
public required IEnumerable<LocalizedNameModel> Name { get; set; }
[ChildRecords]
public IList<PriorityModel>? Children { get; set; }
}
public class LocalizedNameModel
{
public required string Key { get; set; }
public required string Value { get; set; }
}
- Controller
public IActionResult GetPriorities(bool showOnlyTopLevel, bool showAllLanguages, string language = "en")
{
using var cnn = new SqlConnection(connectionString);
var result = cnn.Query("ref.GetPriorities", new { showOnlyTopLevel, showAllLanguages, language },
Query.Returns(Together<PriorityModel, PriorityModel>.Records));
return Ok(result);
}
Expected behavior
I expect following JSON on exit:
[
{
"Id": 1,
"ParentId": null,
"Index": 1,
"Name": {
"Key": "en",
"Value": "Priority 1"
},
"Children": [
{
"Id": 2,
"ParentId": 1,
"Index": 1,
"Name": {
"Key": "en",
"Value": "Priority 1 Subpriority 1"
},
"Children": null
},
{
"Id": 3,
"ParentId": 1,
"Index": 2,
"Name": {
"Key": "en",
"Value": "Priority 1 Subpriority 2"
},
"Children": null
}
]
}
]
- Dotnet version: netcore8.0.12
- Database: SQL Server 2022
- Library version: 8.0.3