Exception thrown by INSERT AFTER trigger not treated properly

[mm3141]

Hi,

we are currently migrating from .net6 (EF6) to .net8 (EF8, Npgsql.EntityFrameworkCore.PostgreSQL 8.0.0, Npgsql 8.0.1). We have some trigger in our DB which, depending on some condition, will perform a RAISE '...' USING ERRCODE='U0001'.
Assume we are doing one UPDATE via EF load/modify/SaveChanges triggering that condition. Previously, with EF6, a NpgsqlException was thrown, which we could handle properly. Now, we are seeing this:

Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.
 ---> System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
   at System.Collections.Generic.List`1.get_Item(Int32 index)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch.Consume(RelationalDataReader reader, Boolean async, CancellationToken cancellationToken)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch.Consume(RelationalDataReader reader)
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.Execute(IRelationalConnection connection)
   --- End of inner exception stack trace ---
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.Execute(IRelationalConnection connection)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.Execute(IEnumerable`1 commandBatches, IRelationalConnection connection)
   at Microsoft.EntityFrameworkCore.Storage.RelationalDatabase.SaveChanges(IList`1 entries)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(IList`1 entriesToSave)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(StateManager stateManager, Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.<>c.<SaveChanges>b__112_0(DbContext _, ValueTuple`2 t)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlExecutionStrategy.Execute[TState,TResult](TState state, Func`3 operation, Func`3 verifySucceeded)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChanges(Boolean acceptAllChangesOnSuccess)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChanges(Boolean acceptAllChangesOnSuccess)

Note that when we are doing the same update via context.Database.ExecuteSql(...), we are seeing the exception we had previously.

Maybe you can tell on the first glance what is going wrong here. If we need to produce an MWE, is there a simple template which we can take and modify?

[roji]

Thanks for reporting, that seems to indicate a bug in the provider. But yeah, that's a pretty complicated method, so I'll need to see some sort of repro for this.

As a template, I usually use this code as a console program. Since you need to define a trigger, you can create the table (and trigger) externally via a SQL script, and then post that here alongside the .NET code.

await using var ctx = new BlogContext();
// await ctx.Database.EnsureDeletedAsync();
// await ctx.Database.EnsureCreatedAsync();

public class BlogContext : DbContext
{
    public DbSet<Blog> Blogs { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        => optionsBuilder
            .UseNpgsql("Host=localhost;Username=test;Password=test")
            .LogTo(Console.WriteLine, LogLevel.Information)
            .EnableSensitiveDataLogging();
}

public class Blog
{
    public int Id { get; set; }
    public string Name { get; set; }
}

[mm3141]

Ok, here is a MWE:

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;

await using var ctx = new BlogContext();
await ctx.Database.EnsureDeletedAsync();
await ctx.Database.EnsureCreatedAsync();
ctx.Add(new Blog { Name = "Blah" });
await ctx.SaveChangesAsync();
await ctx.Database.ExecuteSqlAsync(@$"
CREATE OR REPLACE FUNCTION do_raise() RETURNS trigger LANGUAGE plpgsql AS $function$BEGIN IF NEW.""Name""='Blub' THEN RAISE 'Error' USING ERRCODE='U0001';END IF;END;$function$;
CREATE CONSTRAINT TRIGGER my_trigger AFTER INSERT ON ""Blogs"" DEFERRABLE INITIALLY DEFERRED FOR EACH ROW EXECUTE FUNCTION do_raise();");
ctx.Add(new Blog { Name = "Blub" });
await ctx.SaveChangesAsync();


public class BlogContext : DbContext
{
	public DbSet<Blog> Blogs { get; set; }

	protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
		=> optionsBuilder
			.UseNpgsql("Server=localhost;Port=5435;Database=Cabin;Userid=sa;")
			.LogTo(Console.WriteLine, LogLevel.Information)
			.EnableSensitiveDataLogging();
}

public class Blog
{
	public int Id { get; set; }
	public string Name { get; set; }
}

results in

      An exception occurred in the database while saving changes for context type 'BlogContext'.
      Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.
       ---> System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
         at System.Collections.Generic.List`1.get_Item(Int32 index)
         at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch.Consume(RelationalDataReader reader, Boolean async, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
         --- End of inner exception stack trace ---
         at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(IList`1 entriesToSave, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(StateManager stateManager, Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
         at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func`4 operation, Func`4 verifySucceeded, CancellationToken cancellationToken)
         at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
Unhandled exception. Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.
 ---> System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. (Parameter 'index')
   at System.Collections.Generic.List`1.get_Item(Int32 index)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Update.Internal.NpgsqlModificationCommandBatch.Consume(RelationalDataReader reader, Boolean async, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
   --- End of inner exception stack trace ---
   at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(IEnumerable`1 commandBatches, IRelationalConnection connection, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(IList`1 entriesToSave, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(StateManager stateManager, Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Storage.Internal.NpgsqlExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func`4 operation, Func`4 verifySucceeded, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
   at Program.<Main>$(String[] args) in C:\temp\3007\Program.cs:line 13
   at Program.<Main>$(String[] args) in C:\temp\3007\Program.cs:line 13
   at Program.<Main>(String[] args)

[mm3141]

@roji did you find time to take a look here? MWE is there ^^. Thanks!

[roji]

Thanks for the MWE - I wish I had one like this for each bug filed. Thanks to it I located the bug and submitted a fix - this will be included in the upcoming 8.0.1 release.