Multi-value fields stored as arrays, not comma-delimited strings

Comma-delimited strings cannot be indexed for faceted search, cannot be filtered in SQL without LIKE '%value%' scans, and produce false matches (Parking matches No Parking). Consumer APIs that expect arrays get strings and either crash or display literal WiFi, Parking, Outdoor Seating as a single tag. Migrating later requires a string-split backfill that is brittle when values themselves contain commas, and every downstream integration that already parsed the string must be updated simultaneously.

Store multi-value fields as native arrays in Postgres (text[]) or a relational join table, never as delimited strings. Define them as array types in your Prisma schema at prisma/schema.prisma and update API serializers to emit JSON arrays. Migrate existing comma-delimited rows with a one-time SQL job that splits and trims, then drops the old column.

model Listing {
  id         String   @id @default(cuid())
  name       String
  categories String[]
  amenities  String[]
}

• ID: directory-listing-schema.content-completeness.multi-value-arrays

• Severity: low

• What to look for: List all fields that can contain multiple values (categories, tags, hours, images). For each, check the schema for multi-value fields like categories, amenities, phone numbers, cuisine types, etc. Are they stored as database arrays or strings? Look at JSON responses to see if values are arrays or comma-delimited strings.

• Pass criteria: Multi-value fields are stored as arrays in the database and returned as arrays in API responses — 100% of multi-value fields must be stored and rendered as arrays, not comma-separated strings. Report: "X multi-value fields found, all Y use proper array formatting."

• Fail criteria: Multi-value fields are stored as comma-delimited strings.

• Skip (N/A) when: No multi-value fields exist.

• Detail on fail: Example: "Amenities stored as comma-delimited string 'WiFi, Parking, Outdoor Seating'"

• Remediation: Store multi-value fields as arrays:

  model Listing {
    id String @id @default(cuid())
    name String
    categories String[]
    amenities String[]
  }