NTS translations that use the wrong PostGIS function or drop an argument: `EqualsExact`, `Buffer(d, EndCapStyle)`, `Length`, `NumPoints`, `Combine`, `EnvelopeCombiner`

Offen
  • Stimmt etwas nicht?
#4,092 0 Kommentare 0 Reaktionen 0 zugewiesene Personen Auf GitHub ansehen

Maintainer antworten meist innerhalb von 1 Tag

Dieses Issue hat noch niemand übernommen.

Bewertung

Schwierigkeit
4/5
Geschätzter Aufwand
3-5 Tage
Anfängerfreundlichkeit
70/100
Issue-Typ
Bug
Klarheit
Klar beschrieben
Aktivitätsstatus
Aktiv
Tech-Stack
csharp, postgresql
Bereich
databases

Rechercherichtung

Start by reading the three translator plugins referenced: NpgsqlNetTopologySuiteMethodCallTranslatorPlugin.cs, NpgsqlNetTopologySuiteMemberTranslatorPlugin.cs, and NpgsqlNetTopologySuiteAggregateMethodCallTranslatorPlugin.cs at the cited lines. Adjust the SQL generation for EqualsExact, Buffer, Length, NumPoints, GeometryCombiner.Combine, and EnvelopeCombiner.CombineAsGeometry to match NTS semantics. Done when the LINQ-to-PostGIS translations produce results identical to the .NET outputs shown.

Vom Indexierungsmodell aus dem Issue-Text verfasst.

Beschreibung

Environment
PostgreSQL 18.6 with PostGIS 3.6.4 and GEOS 3.14.1 (postgis/postgis:18-3.6), session TimeZone Etc/UTC
.NET 10 runtime 10.0.11, Npgsql.EntityFrameworkCore.PostgreSQL.NetTopologySuite 10.0.3, EF Core 10.0.4
.NET 11 runtime 11.0.0-rc.2, Npgsql.EntityFrameworkCore.PostgreSQL.NetTopologySuite 11.0.0-rc.2, EF Core 11.0.0-rc.2
Also Npgsql 10.0.3 on both lines, NetTopologySuite 2.6.0, Npgsql.NetTopologySuite 10.0.3, macOS arm64

Both lines print the same output. main at 150011d has the same code.

LINQ Row .NET PostgreSQL SQL
r.Point.EqualsExact(near, 0.5) POINT (1 2), near = POINT (1.1 2) match no match ST_OrderingEquals(r."Point", @near)
r.Line.Buffer(1, EndCapStyle.Flat).Area LINESTRING (0 0, 10 0) 20.00 22.83 ST_Area(ST_Buffer(r."Line", 1.0, 2))
r.Polygon.Length a 4×4 square 16 0 ST_Length(r."Polygon")
r.Polygon.NumPoints same 5 NULL ST_NumPoints(r."Polygon")
GeometryCombiner.Combine(g.Select(r => r.Multi)) two MultiPoints MultiPoint GeometryCollection of 2 ST_Collect(r0."Multi")
EnvelopeCombiner.CombineAsGeometry(...) .SRID SRID 4326 input 4326 −1 ST_Extent(r0."Polygon")::geometry
Repro 
using System.Globalization;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using NetTopologySuite.Geometries;
using NetTopologySuite.Geometries.Utilities;
using NetTopologySuite.Operation.Buffer;

CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
var f = new GeometryFactory(new PrecisionModel(), 4326);
await using var context = new TestContext();
await context.Database.EnsureDeletedAsync();
await context.Database.EnsureCreatedAsync();

context.Rows.AddRange(
    new Row
    {
        Point = f.CreatePoint(new Coordinate(1, 2)),
        Line = f.CreateLineString([new(0, 0), new(10, 0)]),
        Polygon = f.CreatePolygon([new(0, 0), new(4, 0), new(4, 4), new(0, 4), new(0, 0)]),
        Multi = f.CreateMultiPointFromCoords([new(0, 0), new(1, 1)]),
    },
    new Row
    {
        Point = f.CreatePoint(new Coordinate(5, 5)),
        Line = f.CreateLineString([new(0, 0), new(0, 10)]),
        Polygon = f.CreatePolygon([new(0, 0), new(1, 0), new(1, 1), new(0, 1), new(0, 0)]),
        Multi = f.CreateMultiPointFromCoords([new(2, 2), new(3, 3)]),
    });
await context.SaveChangesAsync();
var rows = await context.Rows.AsNoTracking().OrderBy(r => r.Id).ToListAsync();
var row = rows[0];
var near = f.CreatePoint(new Coordinate(1.1, 2));

// 1. The tolerance is dropped: ST_OrderingEquals(a, b)
Console.WriteLine($"Point.EqualsExact(near, 0.5): .NET {rows.Count(r => r.Point.EqualsExact(near, 0.5))}, database {await context.Rows.CountAsync(r => r.Point.EqualsExact(near, 0.5))}");

// 2. The cap style is passed as ST_Buffer's integer quad_segs argument
Console.WriteLine($"Line.Buffer(1, EndCapStyle.Flat).Area: .NET {row.Line.Buffer(1, EndCapStyle.Flat).Area:F2}, database {await context.Rows.OrderBy(r => r.Id).Select(r => r.Line.Buffer(1, EndCapStyle.Flat).Area).FirstAsync():F2}");

// 3. ST_Length is 0 for polygons; NTS and SQL Server return the perimeter
Console.WriteLine($"Polygon.Length: .NET {row.Polygon.Length}, database {await context.Rows.OrderBy(r => r.Id).Select(r => r.Polygon.Length).FirstAsync()}");

// 4. ST_NumPoints is NULL for anything but a LineString; ST_NPoints counts every geometry
Console.WriteLine($"Polygon.NumPoints: .NET {row.Polygon.NumPoints}, database {(await context.Rows.OrderBy(r => r.Id).Select(r => (int?)r.Polygon.NumPoints).FirstAsync())?.ToString() ?? "NULL"}");

// 5. ST_Collect nests collections; GeometryCombiner flattens them
var combined = await context.Rows.GroupBy(r => 1).Select(g => GeometryCombiner.Combine(g.Select(r => (Geometry)r.Multi))).SingleAsync();
Console.WriteLine($"GeometryCombiner.Combine(MultiPoints): .NET {GeometryCombiner.Combine(rows.Select(r => (Geometry)r.Multi)).GeometryType}, database {combined.GeometryType} of {combined.NumGeometries}");

// 6. ST_Extent returns a box2d, which has no SRID
var envelope = await context.Rows.GroupBy(r => 1).Select(g => EnvelopeCombiner.CombineAsGeometry(g.Select(r => (Geometry)r.Polygon))).SingleAsync();
Console.WriteLine($"EnvelopeCombiner.CombineAsGeometry(...).SRID: .NET {EnvelopeCombiner.CombineAsGeometry(rows.Select(r => (Geometry)r.Polygon)).SRID}, database {envelope.SRID}");

public class TestContext : DbContext
{
    public DbSet<Row> Rows => Set<Row>();

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        => optionsBuilder
            .UseNpgsql(Environment.GetEnvironmentVariable("Test__Npgsql__DefaultConnection"), o => o.UseNetTopologySuite())
            .LogTo(Console.WriteLine, LogLevel.Information)
            .EnableSensitiveDataLogging();

    protected override void OnModelCreating(ModelBuilder modelBuilder)
        => modelBuilder.HasPostgresExtension("postgis");
}

public class Row
{
    public int Id { get; set; }
    public Point Point { get; set; }
    public LineString Line { get; set; }
    public Polygon Polygon { get; set; }
    public MultiPoint Multi { get; set; }
}

Output, the same on both lines:

Point.EqualsExact(near, 0.5): .NET 1, database 0
Line.Buffer(1, EndCapStyle.Flat).Area: .NET 20.00, database 22.83
Polygon.Length: .NET 16, database 0
Polygon.NumPoints: .NET 5, database NULL
GeometryCombiner.Combine(MultiPoints): .NET MultiPoint, database GeometryCollection of 2
EnvelopeCombiner.CombineAsGeometry(...).SRID: .NET 4326, database -1
Vorherrschende Sprache
C#
Sterne
1.8k
Forks
268
Ø Merge
2 Std. 35 Min.
Gemergte PRs (30 T.)
136

Entwicklungsumgebung

Dieses Projekt bietet weder Dev-Container noch Dockerfile noch Beitragsleitfaden – die Einrichtung liegt bei Ihnen. Beginnen Sie mit der README; die allgemeinen Schritte stehen in unserem Leitfaden für den ersten Beitrag.

Erste Schritte

  1. Lesen Sie das ganze Issue und danach den Beitragsleitfaden des Projekts.
  2. Schreiben Sie ins Issue, dass Sie es übernehmen — das erspart doppelte Arbeit.
  3. Forken Sie das Repository und arbeiten Sie in einem Branch.
  4. Öffnen Sie einen Pull Request, der die Issue-Nummer nennt.

Mehr aus npgsql/efcore.pg

Alle Issues in npgsql/efcore.pg

Ähnliche Issues

Weitere Issues zu C#

Neue Issues direkt in Ihr Postfach

Eine kurze Übersicht über anfängerfreundliche GitHub-Issues.