Why doesn't SemanticTextMemory.SaveSaveReferenceAsync store the text?

[xbotter]

Based on the source code,

semantic-kernel/dotnet/src/SemanticKernel/Memory/SemanticTextMemory.cs

Lines 49 to 58 in ccb9c26

	public async Task SaveReferenceAsync(
	string collection,
	string text,
	string externalId,
	string externalSourceName,
	string? description = null,
	CancellationToken cancel = default)
	{
	var embedding = await this._embeddingGenerator.GenerateEmbeddingAsync(text);
	var data = MemoryRecord.ReferenceRecord(externalId: externalId, sourceName: externalSourceName, description, embedding);

I found that the method generates an embedding based on the text input, but it doesn't actually store the text in the MemoryRecord. As a result, when I try to search for the text, I can't retrieve it from the MemoryRecord. I'm not sure why it was designed this way and would appreciate some clarification.

[awharrison-28]

Hi @xbotter.

Context: there are 2 save methods associated with SemanticTextMemory - SaveReference and SaveInformation.

SaveReference is intended to save information from a known source - this way you can store an embedding and recreate it from the source without having to take up space also storing the source text.

SaveInformation is intended to save information where the source text cannot be referenced.

Scenario Examples:
SaveReference( collection: "Semantic Kernel GitHub", externalId: "https://github.com/microsoft/semantic-kernel/discussions/438", sourceName: "Semantic Kernel Discussions", text: text, description: "Why doesn't SemanticTextMemory.SaveReference store the text?")

Where the 'text' might be of a summary of this discussion generated by a semantic skill.

SaveReference( collection: "Semantic Kernel GitHub", externalId: "https://github.com/microsoft/semantic-kernel/blob/main/dotnet/src/SemanticKernel/Memory/SemanticTextMemory.cs", sourceName: "SemanticTextMemory.SaveReference", text: text, description: "lines 49-66")

Where the 'text' is the codeblock defining SemanticTextMemory.SaveReference.

vs

SaveInformation( collection: "About Me", id: "myOccupation", text: "Software Engineer")

I hope this helps!

[xbotter]

Thanks for your explanation, I think I got it now!

[afederici75]

Thanks for the answer!