component name is "Unknown" for Npgsql.EntityFrameworkCore.PostgreSQL

[SummerZYQ]

Please answer these questions before submitting your issue.

• Why do you submit this issue?
• Question or discussion
• Bug
• Requirement
• Feature or performance improvement

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Question

• What do you want to know?
  
  this component value is "Unknown", but i'am use "Npgsql.EntityFrameworkCore.PostgreSQL"

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Bug

• Which version of SkyWalking, OS and .NET Runtime?
  skywalking-oap-server:9.1.0
  SkyAPM.Agent.AspNetCore:2.0.1

I think there is only save StringValue, but in SegmentV8Helpers.cs not use it.

SkyAPM-dotnet/src/SkyApm.Diagnostics.EntityFrameworkCore/EntityFrameworkCoreSegmentContextFactory.cs

Line 73 in 51fc719

context.Span.Component = new StringOrIntValue(metadataProvider.Component);

SkyAPM-dotnet/src/SkyApm.Transport.Grpc/Common/SegmentV8Helpers.cs

Line 112 in 51fc719

private static readonly Action<SpanObject, string> ComponentReader = (s, val) => { /*nolonger support*/};

[wu-sheng]

Component ID is only used, name doesn't matter.

[SummerZYQ]

Component ID is only used, name doesn't matter.

metadataProvider.Component is string, use it to context.Span.Component , lose the IntValue.

[wu-sheng]

I don't know dotnet agent, I mean from protocol perspective.