# Migrate from pgsearch to lakebasetext

#### pg\_search is deprecated

`pg_search` (ParadeDB) was deprecated on Neon: new installs were blocked, and existing installs were retired on **September 21, 2026**. [`lakebase_text`](/guides/postgres-extensions-lakebase-text) is its replacement for BM25 search.

This guide migrates your BM25 full-text search from `pg_search` to `lakebase_text`. You map your existing indexes and queries to their `lakebase_text` equivalents, verify the results, then remove `pg_search`. `lakebase_text` runs BM25 search through a `lakebase_bm25` index built on standard Postgres `tsvector` types.

## What changes

`pg_search` and `lakebase_text` both do BM25 search, but they model it differently:

|                  | `pg_search` (ParadeDB)                                                                     | `lakebase_text`                                                                            |
| ---------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------ |
| Index            | `USING bm25 (col1, col2) WITH (key_field='id')`: indexes raw columns, tokenizes internally | `USING lakebase_bm25 (body_tsv)`: indexes a `tsvector` column you build with `to_tsvector` |
| Query operator   | `col @@@ 'query'` (filters and ranks at once)                                              | `@@ to_tsquery('query')` to filter, `<@> to_bm25query(…, 'index_name')` to rank            |
| Ranking          | `paradedb.score(id)` with `ORDER BY score DESC` (higher = better)                          | `<@>` returns a negative score with `ORDER BY score ASC` (lower = better)                  |
| Multiple columns | one index over several columns                                                             | combine the columns into one `tsvector`                                                    |
| Tokenization     | internal (ICU, Lindera, language stemmers)                                                 | Postgres text-search configurations (`'english'`, and others)                              |

The main difference: `pg_search` indexes your columns directly, while `lakebase_text` indexes a `tsvector` that you build (usually a generated column).

::::steps
:::step{title="Enable lakebase_text"}
Before you migrate, `lakebase_text` needs to be enabled on your project. Check what's loaded:

```sql
SHOW shared_preload_libraries;
```

If `lakebase_text` is in the list, create the extension and you're ready:

```sql
CREATE EXTENSION IF NOT EXISTS lakebase_text;
```

If `lakebase_text` isn't listed, enabling it is a one-time setup: add it to your project's preloaded libraries with the Neon API, restart the compute, then create the extension. The [Get started with Lakebase Search](/guides/postgres-ai-lakebase-search-get-started) guide has the full steps. For this migration you need only `lakebase_text`, not `lakebase_vector`. Leave `pg_search` enabled while you migrate.
:::

:::step{title="Migrate the index"}
The examples below use a `mock_items(description, category)` table as a stand-in for your existing table. Substitute your own table and column names.

With `pg_search`, you create a BM25 index over your columns and designate a `key_field`:

```sql
-- pg_search
CREATE INDEX mock_items_search ON mock_items
  USING bm25 (id, description, category) WITH (key_field = 'id');
```

With `lakebase_text`, you build a `tsvector` from the same columns and index that. A `GENERATED ALWAYS` column keeps it in sync as rows change:

```sql
-- lakebase_text
ALTER TABLE mock_items ADD COLUMN search_tsv tsvector
  GENERATED ALWAYS AS (to_tsvector('english', coalesce(description, '') || ' ' || coalesce(category, ''))) STORED;

CREATE INDEX mock_items_bm25 ON mock_items USING lakebase_bm25 (search_tsv);
```

To search a single column instead of several, point `to_tsvector` at just that column. `'english'` is one of several built-in [Postgres text-search configurations](https://www.postgresql.org/docs/current/textsearch.html); list the ones available on your database with `SELECT cfgname FROM pg_ts_config;`. BM25 scores depend on corpus statistics gathered at build time, so create the index after your data is loaded, and run `VACUUM` after large bulk loads to keep scores accurate.
:::

:::step{title="Migrate your queries"}
`pg_search` queries a column with the `@@@` operator and ranks with `paradedb.score()`, highest first:

```sql
-- pg_search
SELECT id, description, paradedb.score(id) AS score
FROM mock_items
WHERE description @@@ 'keyboard'
ORDER BY score DESC;
```

```
id |         description          |   score
----+------------------------------+-----------
  2 | Blue metal keyboard          | 0.8236319
  3 | Wireless ergonomic keyboard  | 0.8236319
```

`lakebase_text` does the same work with two operators instead of one: `@@` filters the matching rows, and `<@>` with `to_bm25query` ranks them. Scores are negative, so order ascending to put the best matches first:

```sql
-- lakebase_text
SELECT id, description,
  search_tsv <@> to_bm25query(to_tsvector('english', 'keyboard'), 'mock_items_bm25') AS score
FROM mock_items
WHERE search_tsv @@ to_tsquery('english', 'keyboard')
ORDER BY score
LIMIT 10;
```

```
id |         description          |        score
----+------------------------------+---------------------
  2 | Blue metal keyboard          | -0.8374048792080783
  3 | Wireless ergonomic keyboard  | -0.8374048792080783
```

When you rewrite a query, three things change:

- **Filter with `@@`.** `<@>` only scores, it doesn't filter. Add a `WHERE search_tsv @@ to_tsquery('english', 'query')` clause, or every row comes back (non-matches at score 0).
- **Pass the index name to `to_bm25query`.** BM25 scoring reads corpus statistics from the index.
- **Reverse the sort.** `pg_search` orders `DESC`; `lakebase_text` orders ascending, because its scores are negative and a lower score is a better match.

For multi-word or user-supplied input, use `websearch_to_tsquery('english', 'your query')` in place of `to_tsquery` in both the filter and the rank. `to_tsquery` expects pre-formatted query syntax and errors on plain phrases with spaces.
:::

:::step{title="Check for feature gaps"}
Before you drop `pg_search`, confirm the features you rely on carry over. A few don't map one-to-one:

- **Fuzzy / typo matching** (`paradedb.match(..., distance => 1)`): no direct equivalent. Use [`pg_trgm`](/guides/postgres-extensions-pg-trgm) for similarity and typo-tolerant matching.
- **Highlighting** (`paradedb.snippet()`): use Postgres [`ts_headline()`](https://www.postgresql.org/docs/current/textsearch-controls.html#TEXTSEARCH-HEADLINE).
- **JSON query objects and advanced tokenizers** (ICU, Lindera): not supported. Use `tsquery` operators (`&`, `|`, `<->`) and [Postgres text-search](https://www.postgresql.org/docs/current/textsearch.html) configurations.
:::

:::step{title="Remove pg_search"}
Once your queries run on `lakebase_text` and return the results you expect, drop `pg_search` ahead of the September 21, 2026 removal:

```sql
DROP EXTENSION pg_search CASCADE;
```

`CASCADE` also drops the `bm25` indexes that depend on the extension. Confirm it's gone:

```sql
SELECT extname FROM pg_extension WHERE extname = 'pg_search';   -- returns no rows
```

Finally, restart the compute to complete the migration. In the [Neon Console](https://console.neon.tech/), open the compute's **⋯** menu and select **Restart compute**, or call the [Restart compute endpoint](/guides/apis-sdks-reference-api-endpoints-restart-project-endpoint) API.

Your search now runs entirely on `lakebase_text`.
:::
::::

## Resources

- [The lakebase\_text extension](/guides/postgres-extensions-lakebase-text)
- [The pg\_search extension](/guides/postgres-extensions-pg-search) (deprecated)
- [Lakebase Search](/guides/postgres-ai-lakebase-search)

## Related pages

- [Get started with Lakebase Search](./postgres-ai-lakebase-search-get-started.md)

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