exports.up = (pgm) => {
  pgm.sql(`
    -- Nullable timestamp rather than a boolean: disabling is reversible, and
    -- this records when it happened without a second column.
    ALTER TABLE customers ADD COLUMN IF NOT EXISTS disabled_at TIMESTAMPTZ;

    -- attachCustomer joins customers on every authenticated request to check
    -- this, so the lookup wants an index on the active case.
    CREATE INDEX IF NOT EXISTS customers_disabled_at_idx
      ON customers (disabled_at) WHERE disabled_at IS NOT NULL;
  `);
};

exports.down = (pgm) => {
  pgm.sql(`
    DROP INDEX IF EXISTS customers_disabled_at_idx;
    ALTER TABLE customers DROP COLUMN IF EXISTS disabled_at;
  `);
};