perf(providers): optimize gateway error rate query to avoid unnecessary view joins

[kilo-code-bot]

Summary

The getGatewayErrorRate query was using microdollar_usage_view, which joins 13+ tables via LEFT JOINs (IP lookups, user agent, editor name, finish reason, etc.). The query only needs 4 columns: provider, has_error, created_at (from microdollar_usage), and is_user_byok (from microdollar_usage_metadata).

Replaced the view query with a direct INNER JOIN between just microdollar_usage and microdollar_usage_metadata, eliminating 12 unnecessary LEFT JOINs. This should significantly reduce query execution time, which is important since this query has a 500ms timeout and is called on every request.

Verification

• Reviewed the view definition in packages/db/src/schema.ts to confirm column sources
• Verified the optimized query uses the correct table aliases and column references
• Confirmed created_at index exists on microdollar_usage (idx_created_at)

Visual Changes

N/A

Reviewer Notes

• Changed from LEFT JOIN (in the view) to INNER JOIN for microdollar_usage_metadata. This means rows without metadata will be excluded. This is intentional since is_user_byok lives on the metadata table and rows without metadata can't be filtered on it. If a metadata row is missing, is_user_byok would be NULL and the = false filter would exclude it anyway.
• The query has a 500ms timeout with a fallback to { openrouter: 0, vercel: 0 }, so this optimization helps avoid unnecessary timeouts.

[kilo-code-bot]

Code Review Summary

Status: No Issues Found | Recommendation: Merge

Files Reviewed (1 files)

• src/lib/providers/gateway-error-rate.ts

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_{Reviewed by gpt-5.4-20260305 · 116,925 tokens}