Add Support for Vector Data Type in SQL for REST

[RubenCerna2079]

Why make this change?

• Solves issue Foundation for adding support for Vector Data Type #3654

What is this change?

These changes add the base to support the Vector data type for REST, GraphQL, and MCP. This PR focuses mainly on the REST endpoint, ensuring that it is able to both read and write to the vector columns through it. Lastly, it also adds support to ensure that OpenAPI is able to show columns with the Vector data type as array: [numeric].

The following files were changed to show that DAB is able to support the Vector data type and also change the type internally to system types it can work with. Such as the float type for DbType, the Numeric type for JsonDataType, and SINGLE_TYPE for GraphQL.

• SqlTypeConstants
• TypeHelper.cs
• SqlSchemaConverter.cs

The following file was changed to allow DAB to save the vector columns as an array type, which is necessary for GraphQL to be able to know if the column of an entity is a simple type or an array.

• MsSqlMetadataProvider.cs

The following files were changed to parse the information from the user to a format that can be used by DAB to create the queries for SQL.

• BaseSqlQueryStructure.cs: Parses the array information by creating a new function that checks for the simple type of the array (e.g If it is an array of floats it will use the type float) and parse each value inside the array.
• MsSqlQueryExecutor.cs: Parses the values given by the user and adds them to an SqlVector object which allows for an easier way to query the values.

The following file was changed to allow DAB's OpenAPI to support array types by checking if the main type is array and then taking the subtype and creating the appropriate item with it.

• OpenApiDocumentor.cs

Note: All of these changes are only applicable to Vectors of Float32, support for Vectors of Float16 will have to wait as support for it in .NET is still missing.

How was this tested?

• Integration Tests
• Unit Tests

Added tests that ensure the following scenarios on REST:

• Read regular vector
• Read vector with max number of dimensions possible
• Read vector with null value
• Read vector with $first argument
• Read vector with $after argument
• Read vector with $filter argument - fails
• Read vector with $orderby argument - fails
• Insert regular vector
• Insert vector with null value
• Insert vector with number values in scientific format
• Insert vector with number values in string format
• Insert vector with more dimensions than allowed - fails
• Insert vector with non-valid values - fails
• Update vector with new values

Sample Request(s)

Note: Currently the values will be outputted in scientific notation, this will be changed in the future #3680

GET https://localhost:5001/api/dbo_normalvector/

POST https://localhost:5001/api/dbo_normalvector/

{
	"ProductID": 2001,
	"Embedding": [
		1.15202468461012559910005,
		0.00005,
		5.111111111
	]
}

PATCH https://localhost:5001/api/dbo_normalvector/ (Adding new row)

{
	"ProductID": 3000,
	"Embedding": [
		1.15202468461012559910005,
		0.00005,
		5.111111111
	]
}

PATCH https://localhost:5001/api/dbo_normalvector/ (Update existing row)

{
	"ProductID": 2001,
	"Embedding": [
		25,
		1.2,
		510.35
	]
}

PUT https://localhost:5001/api/dbo_normalvector/ (Adding new row)

{
	"ProductID": 4000,
	"Embedding": [
		0,
		1,
		37
	]
}

PUT https://localhost:5001/api/dbo_normalvector/ (Edit existing row)

{
	"ProductID": 2001,
	"Embedding": [
		0.220224962,
		0.66666667,
		37
	]
}

https://localhost:5001/swagger

[Copilot]

Pull request overview

Adds SQL Server vector(N) column support in DAB’s SQL layer so REST endpoints can read/write vectors as JSON number arrays, with accompanying integration tests and metadata/type mappings.

Changes:

• Adds REST integration tests and MSSQL schema/config updates for a VectorType table/entity.
• Extends MSSQL metadata/type handling to recognize vector columns and treat them as array-like for downstream processing.
• Adds parameter parsing/execution support to accept JSON arrays and pass them to SqlClient as SqlVector<float>.

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
src/Service.Tests/SqlTests/RestApiTests/MsSqlRestVectorTypesTests.cs	New REST integration tests covering vector read/write and pagination behavior.
src/Service.Tests/DatabaseSchema-MsSql.sql	Adds vector_type_table and seed data, including a max-dimension vector row.
src/Service.Tests/dab-config.MsSql.json	Adds VectorType entity configuration and updates the MSSQL connection string.
src/Service.GraphQLBuilder/Sql/SchemaConverter.cs	Adds GraphQL type mapping for SqlVector<T>.
src/Core/Services/TypeHelper.cs	Adds DbType/JsonDataType/SqlDbType mappings related to vector support.
src/Core/Services/MetadataProviders/MsSqlMetadataProvider.cs	Detects vector columns and marks them as array-like for metadata consumers.
src/Core/Resolvers/Sql Query Structures/BaseSqlQueryStructure.cs	Adds parsing logic for Single[] values from JSON arrays.
src/Core/Resolvers/MsSqlQueryExecutor.cs	Converts vector parameters to SqlVector<float> before sending to SQL Server.
src/Core/Resolvers/MsSqlQueryBuilder.cs	Removes vector from the “unsupported types” list so it can be handled.
src/Core/Models/SqlTypeConstants.cs	Marks vector as a supported SQL type literal.
src/Config/Azure.DataApiBuilder.Config.csproj	File encoding change (BOM added).
config-generators/mssql-commands.txt	Adds generator commands for the new VectorType entity.