Summary
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This commit unifies soft-delete behaviour across meta tables and
introduces an in-memory cache for model pricing look-ups to improve
throughput under high concurrency.
Details
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Soft-delete consistency
• PrefillGroup / Vendor / Model
– Added `gorm.DeletedAt` field with `json:"-" gorm:"index"`.
– Replaced plain `uniqueIndex` with partial unique indexes
`uniqueIndex:<name>,where:deleted_at IS NULL`
allowing duplicate keys after logical deletion while preserving
uniqueness for active rows.
• Imports updated to include `gorm.io/gorm`.
• JSON output now hides `deleted_at`, matching existing tables.
High-throughput pricing cache
• model/pricing.go
– Added thread-safe maps `modelEnableGroups` & `modelQuotaTypeMap`
plus RW-mutex for O(1) access.
– `updatePricing()` now refreshes these maps alongside `pricingMap`.
• model/model_extra.go
– Rewrote `GetModelEnableGroups` & `GetModelQuotaType` to read from
the new maps, falling back to automatic refresh via `GetPricing()`.
Misc
• Retained `RefreshPricing()` helper for immediate cache invalidation
after admin actions.
• All modified files pass linter; no breaking DB migrations required
(handled by AutoMigrate).
Result
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– Soft-delete logic is transparent, safe, and allows record “revival”.
– Pricing-related queries are now constant-time, reducing CPU usage and
latency under load.
