Why does AddEntityOptions exists and why does it derive from UpsertEntityOptions (when UpdateEntityOptions and MergeEntityOptions don't)

[ahsonkhan]

This options bag doesn't seem to be used to modify client behavior for TableClient::AddEntity:

azure-sdk-for-cpp/sdk/tables/azure-data-tables/inc/azure/data/tables/models.hpp

Lines 576 to 585 in 384552a

	struct AddEntityOptions : public UpsertEntityOptions
	{
	AddEntityOptions() = default;
	/**
	* @brief Create Entity options constructor.
	*
	* @param other Upsert Entity options.
	*/
	explicit AddEntityOptions(UpsertEntityOptions const& other) { (void)other; }
	};

azure-sdk-for-cpp/sdk/tables/azure-data-tables/src/table_clients.cpp

Lines 445 to 450 in 384552a

	Azure::Response<Models::AddEntityResult> TableClient::AddEntity(
	Models::TableEntity const& tableEntity,
	Models::AddEntityOptions const& options,
	Core::Context const& context)
	{
	(void)options;

Following-up from #6229 (comment)

.NET doesn't expose this:
https://github.com/Azure/azure-sdk-for-net/blob/4e1173308d32f0413788359a87376e673f2ab15b/sdk/tables/Azure.Data.Tables/src/TableClient.cs#L603

GoLang has it, but it contains MetadataFormat, rather than it being empty/inheriting from UpsertOptions:
https://github.com/Azure/azure-sdk-for-go/blob/3ebd0d439f9d8aa06a0764a60892a8001b997a34/sdk/data/aztables/client.go#L247

cc @LarryOsterman (since this is regarding API review)

[gearama]

works as exopected

[ahsonkhan]

The bare-minimum fix here (without knowing a lot about the intended usage) would be to remove this inheritance from UpsertEntityOptions, so the options for Add, Update, Merge are consistent:

azure-sdk-for-cpp/sdk/tables/azure-data-tables/inc/azure/data/tables/models.hpp

Line 576 in 384552a

struct AddEntityOptions : public UpsertEntityOptions

That said, @LarryOsterman believes we have another issue:

The explicit constructor for AddEntityOptions which takes an UpsertEntityOptions is incorrect because it doesn't initialize the base class - instead it ignores the options passed in.