add support for ranking functions

[JasonShin]

No description provided.

[Copilot]

Pull request overview

This PR updates the type inference for SQL window/ranking functions so generated TypeScript result types are more specific than any.

Changes:

• Refines ranking/window function result fields from any to number in demo query typings (e.g., ROW_NUMBER, RANK, DENSE_RANK, NTILE).
• Treats several window value functions as type-polymorphic in the SQL parser (e.g., LAG, LEAD, FIRST_VALUE).
• Updates snapshot typings to match the new inferred result types.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
tests/demo/window/row_number.snapshot.ts	Updates rowNum to number in snapshots to reflect new typing.
tests/demo/window/row_number.queries.ts	Updates rowNum to number in query typings.
tests/demo/window/rank_functions.snapshot.ts	Updates ranking-related fields (rank, denseRank, quartile, rowNum) to number in snapshots.
tests/demo/window/rank_functions.queries.ts	Updates ranking-related fields to number in query typings.
tests/demo/window/lag_lead.snapshot.ts	Updates window value fields (previousName, nextName, etc.) from any to string in snapshots.
tests/demo/window/lag_lead.queries.ts	Updates window value fields from any to string in query typings.
tests/demo/cte/cte.snapshot.ts	Updates rk (rank) field from any to number in snapshot.
tests/demo/cte/cte.queries.ts	Updates rk (rank) field from any to number in query typings.
src/ts_generator/sql_parser/expressions/functions.rs	Classifies ranking functions as numeric and value window functions as type-polymorphic.

Comments suppressed due to low confidence (6)

tests/demo/window/lag_lead.queries.ts:1

• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.
  tests/demo/window/lag_lead.queries.ts:1
• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.
  tests/demo/window/lag_lead.queries.ts:1
• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.
  tests/demo/window/lag_lead.queries.ts:1
• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.
  tests/demo/window/lag_lead.queries.ts:1
• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.
  tests/demo/window/lag_lead.queries.ts:1
• LAG/LEAD (and often NTH_VALUE) can return NULL when the requested row is out of range (e.g., LAG on the first row, LEAD on the last row) unless the SQL uses a default value. Typing these fields as string is likely incorrect for the general case and can break consumers at runtime. Suggest changing the inferred return type for LAG/LEAD (and NTH_VALUE, if supported) to include nullability (e.g., string | null here), or adjust the demo queries/tests to explicitly filter out rows where these values are NULL if you intentionally want a non-null string type.

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