Function localeFilter

apps/docs/app/api/chat/route.ts:190–200

* SQL predicate selecting only the locale's documents, so the row limit applies * to matching rows: non-English docs are prefixed with their locale segment; * English is everything not prefixed with another locale.

(locale: string)

 * English is everything not prefixed with another locale.
 */
function localeFilter(locale: string) {
  const firstSegment = sql`split_part(${docsEmbeddings.sourceDocument}, '/', 1)`
  if (locale === DEFAULT_LOCALE) {
    const others = KNOWN_LOCALES.filter((l) => l !== DEFAULT_LOCALE)
    return sql`${firstSegment} not in (${sql.join(
      others.map((l) => sql`${l}`),
      sql`, `
    )})`
  }
  return sql`${firstSegment} = ${locale}`
}

type SearchRow = {
  chunkId: string