fix: fix vector index prewarm index

[xloya]

Close #5411. First, try to retrieve the field from the schema. If it cannot be retrieved, then retrieve it directly from the fields of index_meta.

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[codecov]

Codecov Report

❌ Patch coverage is 95.06173% with 8 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
rust/lance/src/index.rs	95.06%	7 Missing and 1 partial ⚠️

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[Xuanwo]

Thank you for working on this!

I took a quick look and the fix seems correct, but there’s an issue with index access inside nested structs. I wonder if we can improve this.

Let’s build an API called resolve_index_column(idx_meta, column_arg, schema) -> Result<(String, FieldRef)>, where the String is the full path of the given index.

The full path can be used in all following API calls like get_vector_type.

This API could be used across all vector, scalar, and generic open/prewarm operations.

What do you think?

[xloya]

Thank you for working on this!

I took a quick look and the fix seems correct, but there’s an issue with index access inside nested structs. I wonder if we can improve this.

Let’s build an API called resolve_index_column(idx_meta, column_arg, schema) -> Result<(String, FieldRef)>, where the String is the full path of the given index.

The full path can be used in all following API calls like get_vector_type.

This API could be used across all vector, scalar, and generic open/prewarm operations.

What do you think?

That sounds like a good idea, let me try to improve it.

[xloya]

@Xuanwo Address the comment, please take another look when you have time, thanks!

[Xuanwo]

Thank you for fixing this!