GetSchema("DataTypes") does not return entries for JSON and VECTOR types

[igor-tkachev]

Describe the bug

SqlConnection.GetSchema("DataTypes") does not include rows for the built-in SQL Server types JSON and VECTOR.

To reproduce

using Microsoft.Data.SqlClient;

using var connection = new SqlConnection("Server=.;Database=master;Integrated Security=true;");
connection.Open();

var table = connection.GetSchema("DataTypes");

bool hasJson   = table.Rows.Cast<DataRow>().Any(r => ((string)r["TypeName"]).Equals("json",   StringComparison.OrdinalIgnoreCase));
bool hasVector = table.Rows.Cast<DataRow>().Any(r => ((string)r["TypeName"]).Equals("vector", StringComparison.OrdinalIgnoreCase));

Console.WriteLine($"JSON found:   {hasJson}");
Console.WriteLine($"VECTOR found: {hasVector}");

Actual: both return false
Expected: both types should be included

Further technical details

Microsoft.Data.SqlClient version: all versions, including prerelease
.NET target: all
SQL Server version: SQL Server 2025
Operating system: any

[mdaigle]

cc @apoorvdeshmukh this looks like another vector enhancement

[igor-tkachev]

Just to clarify, this isn’t only a vector-specific enhancement.

When new types are added to the provider, their metadata also needs to appear in GetSchema("DataTypes"), because many tools that work with database metadata, both at runtime and for code generation, rely on this information.

Since JSON and VECTOR are missing from the metadata, this is mostly about keeping provider type metadata in sync with newly supported types.

Thanks!

[mdaigle]

Thanks @igor-tkachev, we have prioritized it accordingly and will try to pick up the work soon.