charettes · HackerTrans

5 bulan yang laludiscuss

There are valid reasons for not using an ORM but the points made in this article are plain false.

>“Roughly” because Django ORM doesn’t support the JSONB `?` operator.

The `has_key` [lookup](https://docs.djangoproject.com/en/6.0/topics/db/queries/#has...) does exactly that.

> And if you need real SQL intervals, Django pushes you towards raw expressions or `Func()` wrappers.

It's possible to use a very similar construct to SQL Alchemy here by using the `Now` [function](https://docs.djangoproject.com/en/6.0/ref/models/database-fu...) (it uses `STATEMENT_TIMESTAMP` which is likely more correct than `NOW()` here alternatively there is `TransactionNow`) by doing `Now() - timedelta(days=30)`.

The result is the following `filter` call

  filter(
      metadata__tags__has_key="python",
      created_at__gte=(
        Now() - timedelta(days=30)
      ),
   )

which translates to the following SQL

  ("app_video"."metadata" -> 'tags') ? 'python'
  AND "app_video"."created_at" >= (
    STATEMENT_TIMESTAMP() - '30 days'::interval
  )

which can be confirmed in [this playground](https://dryorm.xterm.info/hn-47110310)

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