import { BaseSchema } from '@adonisjs/lucid/schema'

/**
 * The prober's start puts a previous run's claims back (probe_candidates status taken → waiting), which scanned
 * the 7.8 GB candidates table on the HDD for 4 minutes after every deploy (LOG.md (133)): a partial index on the
 * few taken rows makes it instant.
 */
export default class extends BaseSchema {
  static disableTransactions = true

  async up() {
    this.schema.raw(
      `CREATE INDEX CONCURRENTLY IF NOT EXISTS probe_candidates_taken_idx ON probe_candidates (id) WHERE status = 'taken'`
    )
  }

  async down() {
    this.schema.raw(`DROP INDEX CONCURRENTLY IF EXISTS probe_candidates_taken_idx`)
  }
}