ODP.NET

Hi,

I'm encountering a critical issue when using Entity Framework Core together with Oracle.ManagedDataAccess.OpenTelemetry and Oracle sequences.

Scenario

I'm using EF Core to insert data into a table where the primary key is generated from a sequence. The model is configured using the UseSequence() API to instruct EF Core to use the Oracle sequence, like so:

modelBuilder.Entity<MyEntity>()
	.Property(e => e.Id)
	.HasColumnName("ID")
	.ValueGeneratedOnAdd()
	.UseSequence("MY_SEQ");

//OR

modelBuilder.Entity<MyEntity>()
	.Property(e => e.Id)
	.HasColumnName("ID") 
	.ValueGeneratedOnAdd()
	.HasDefaultValueSql("MY_SEQ.NEXTVAL");

Separately, I'm also instrumenting database calls using Oracle.ManagedDataAccess.OpenTelemetry. When I enable SQL ID tracing like this:

OracleConfiguration.OpenTelemetry.EnableSqlIdTracing = true;

//OR with DI

builder.Services.AddOpenTelemetry().WithTracing(tracing =>
{
    tracing.AddOracleDataProviderInstrumentation(opts =>
    {
        opts.EnableSqlIdTracing = true;
    });
});

and try to perform an insert using EF Core, the application fails and the Oracle client throws this exception: OracleException: ORA-12537: TNS:connection closed

Observations

• The error only occurs when all three conditions are met:
  1. EF Core uses UseSequence() with default value as SEQ.NEXTVAL
  2. Oracle.ManagedDataAccess.OpenTelemetry is being used
  3. EnableSqlIdTracing = true
• If I disable SQL ID tracing, the insert works as expected.
• If I don’t use sequences, or insert manually using raw SQL, it also works fine even with SQL ID tracing enabled.

Environment

• Oracle.ManagedDataAccess.Core version: 23.8.0
• Oracle.EntityFrameworkCore version: 8.23.60
• Oracle.ManagedDataAccess.OpenTelemetry version: 23.8.0
• EF Core version: 8.0.3
• .NET version: 8