> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blnkfinance.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Performance Tuning

> Optimize filter queries with indexes and learn when to use Typesense for large-scale searches.

## Overview

Blnk is optimized out of the box for most workloads. This guide is for teams processing millions of records who want to squeeze out extra performance when searching directly from the DB.

***

## Default indexes

These fields are already indexed and optimized:

| Table          | Indexed fields                                                                                                                      |
| -------------- | ----------------------------------------------------------------------------------------------------------------------------------- |
| `transactions` | `transaction_id`, `reference`, `status`, `currency`, `source`, `destination`, `parent_transaction`, `created_at`, `meta_data` (GIN) |
| `balances`     | `balance_id`, `ledger_id`, `identity_id`, `indicator`, `currency`, `created_at`                                                     |
| `ledgers`      | `ledger_id`, `created_at`                                                                                                           |
| `identity`     | `identity_id`, `country`, `created_at`                                                                                              |
| `accounts`     | `account_id`, `ledger_id`, `identity_id`, `balance_id`, `created_at`                                                                |

<Tip>
  You can sort and filter efficiently on any of these indexed fields without additional configuration.
</Tip>

***

## Use Typesense for large-scale queries

For complex searches, filtering across millions of records, or when you need sub-millisecond response times, use Blnk's Typesense integration instead of database queries.

Typesense is optimized for:

* Full-text search across any field
* Faceted filtering with instant results
* Sorting large datasets without custom indexes

<Info>
  See [Search via Typesense docs](/search/typesense/introduction) for more.
</Info>

***

## Adding custom indexes

If you're not using Typesense and frequently sort or filter by a specific field at scale, add an index.

<Steps>
  <Step title="Create single column indexes">
    Create indexes for frequently filtered or sorted fields:

    ```sql wrap theme={"system"}
    -- Sort transactions by amount
    CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_transactions_amount 
    ON blnk.transactions (amount);

    -- Sort balances by current balance
    CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_balances_balance 
    ON blnk.balances (balance);
    ```
  </Step>

  <Step title="Create composite indexes">
    For queries that filter and sort on multiple fields, composite indexes are more efficient:

    ```sql wrap theme={"system"}
    -- Filter + sort combo (most efficient for this pattern)
    CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_transactions_status_amount 
    ON blnk.transactions (status, amount);
    ```
  </Step>

  <Step title="Create metadata indexes">
    If you frequently filter on a specific metadata key, index that key directly:

    ```sql wrap theme={"system"}
    -- Index a specific metadata key
    CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_transactions_customer_type 
    ON blnk.transactions ((meta_data->>'customer_type'));
    ```

    <Tip>
      The `meta_data` field already has a GIN index for general JSONB queries, but indexing specific keys provides better performance for frequent filters on those keys.
    </Tip>
  </Step>
</Steps>

<Warning>
  Use `CONCURRENTLY` when creating indexes on production databases to avoid locking tables. This allows the index to be built without blocking reads and writes.
</Warning>

***

## Debugging slow queries

Use `EXPLAIN ANALYZE` to see how Postgres executes a query:

```sql wrap theme={"system"}
EXPLAIN ANALYZE
SELECT *
FROM blnk.transactions
WHERE status = 'APPLIED'
ORDER BY amount DESC
LIMIT 50;
```

What to look for:

* **`Seq Scan`** on large tables: strong signal you need an index
* **High actual time values**: indicates slow query execution
* **Large row counts being filtered down late**: suggests missing indexes

```json Example Output wrap theme={"system"}
QUERY PLAN
─────────────────────────────────────────────────────────────────────────────
 Limit  (cost=0.00..1234.56 rows=50 width=200) (actual time=0.123..45.678 rows=50 loops=1)
   ->  Seq Scan on transactions  (cost=0.00..12345.67 rows=50000 width=200) (actual time=0.120..45.600 rows=50000 loops=1)
         Filter: (status = 'APPLIED'::text)
         Rows Removed by Filter: 100000
 Planning Time: 0.123 ms
 Execution Time: 45.789 ms
```

In this example, a sequential scan is being performed, which suggests adding an index on `status` would improve performance.

***

## Best practices

1. **Monitor query performance**: Use `EXPLAIN ANALYZE` regularly to identify slow queries.

2. **Index strategically**: Only add indexes for fields you filter or sort on frequently. Too many indexes can slow down writes.

3. **Use composite indexes**: When filtering and sorting on multiple fields together, create composite indexes.

4. **Consider Typesense**: For complex queries or very large datasets, Typesense often provides better performance than database indexes.

5. **Test in production-like environments**: Index performance can vary based on data distribution and query patterns.

***

## Need help?

We are very happy to help you make the most of Blnk, regardless of whether it is your first time or you are switching from another tool.

To ask questions or discuss issues, please [contact us](mailto:support@blnkfinance.com) or [join our Discord community](https://discord.gg/7WNv94zPpx).

***

<Tip>
  **Tip:** Connect to Blnk Cloud to see your Core data.

  You can view your transactions, manage identities, create custom reports, invite other team members to collaborate, and perform operations on your Core — all in one dashboard.

  [Check out Blnk Cloud →](https://www.blnkfinance.com/products/cloud)
</Tip>