> For the complete documentation index, see [llms.txt](https://docs.pinot.apache.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.pinot.apache.org/release-1.0.0/basics/indexing/bloom-filter.md).

# Bloom Filter

This page describes configuring the bloom filter for Apache Pinot

The bloom filter prunes segments that do not contain any record matching an **EQUALITY** predicate.

This is useful for a query like the following:

```sql
SELECT COUNT(*) 
FROM baseballStats 
WHERE playerID = 12345
```

There are 3 parameters to configure the bloom filter:

* **`fpp`**: False positive probability of the bloom filter (from `0` to `1`, `0.05` by default). The lower the `fpp` , the higher accuracy the bloom filter has, but it will also increase the size of the bloom filter.
* **`maxSizeInBytes`**: Maximum size of the bloom filter (unlimited by default). If a `fpp` setting generates a bloom filter larger than this size, using this setting will increase the `fpp` to keep the bloom filter size within this limit.
* **`loadOnHeap`**: Whether to load the bloom filter using heap memory or off-heap memory (`false` by default).

There are 2 ways to configure a bloom filter for a table in the [table configuration](/release-1.0.0/configuration-reference/table.md):

* Default settings

```javascript
{
  "tableIndexConfig": {
    "bloomFilterColumns": [
      "playerID",
      ...
    ],
    ...
  },
  ...
}
```

* Customized parameters

```javascript
{
  "tableIndexConfig": {
    "bloomFilterConfigs": {
      "playerID": {
        "fpp": 0.01,
        "maxSizeInBytes": 1000000,
        "loadOnHeap": true
      },
      ...
    },
    ...
  },
  ...
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.pinot.apache.org/release-1.0.0/basics/indexing/bloom-filter.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.