---
title: Limitations
---

## Filtering

In order for ParadeDB's fast field optimizations to apply, the full text search `@@@` operator must be present and used for all predicates,
including filters. For instance, the following two queries produce identical results, but the second query will return faster because only `@@@`, not `=`, is used.

```sql
-- Slow query
SELECT COUNT(*) FROM mock_items
WHERE description @@@ 'shoes' AND rating = 5;

-- Fast query
SELECT COUNT(*) FROM mock_items
WHERE id @@@ paradedb.boolean(
  must => ARRAY[
    paradedb.term('description', 'shoes'),
    paradedb.term('rating', 5)
  ]
);
```

## Text Fast Fields

A known limitation of our underlying search library, Tantivy, is that text fast fields are slower to return than non-text fast fields.
Future releases will improve the speeds of text fast fields. In the meantime, we recommend using a non-text field for aggregates whenever possible. For instance,
using `COUNT(*)` instead of `COUNT(<text_field>)`.
