---
id: data-parquet-page-indexes-and-bloom-filters
title: 'Data Parquet Page Indexes and Bloom Filters'
schema_type: TechArticle
category: computer-science
language: en
confidence: medium
last_verified: '2026-06-03'
created_date: '2026-06-03'
generation_method: ai_structured
derived_from_human_seed: true
conflict_of_interest: none_declared
is_live_document: false
data_period: static
atomic_facts:
  - id: fact-cs-data-parquet-page-indexes-and-bloom-filters-1
    statement: >-
      Apache Parquet documentation describes a page index as optional
      ColumnChunk metadata containing DataPage statistics that can be used to
      skip pages during scans.
    source_title: Apache Parquet Page Index
    source_url: https://parquet.apache.org/docs/file-format/pageindex/
    confidence: medium
  - id: fact-cs-data-parquet-page-indexes-and-bloom-filters-2
    statement: >-
      Apache Parquet documentation says the page index adds ColumnIndex and
      OffsetIndex structures to row group metadata.
    source_title: Apache Parquet Page Index
    source_url: https://parquet.apache.org/docs/file-format/pageindex/
    confidence: medium
  - id: fact-cs-data-parquet-page-indexes-and-bloom-filters-3
    statement: >-
      Apache Parquet documentation says Bloom filters can enable predicate
      pushdown for high-cardinality columns.
    source_title: Apache Parquet Bloom Filter
    source_url: https://parquet.apache.org/docs/file-format/bloomfilter/
    confidence: medium
completeness: 0.82
known_gaps:
  - Page-skipping behavior depends on writer support, reader support, sort order, statistics truncation, null handling, predicate shape, bloom-filter false positives, compression, and whether the query engine consults page-level metadata.
disputed_statements: []
primary_sources:
  - title: Apache Parquet Page Index
    type: documentation
    year: 2026
    url: https://parquet.apache.org/docs/file-format/pageindex/
    institution: Apache Parquet
  - title: Apache Parquet Bloom Filter
    type: documentation
    year: 2026
    url: https://parquet.apache.org/docs/file-format/bloomfilter/
    institution: Apache Parquet
secondary_sources: []
updated: '2026-06-03'
ai_models:
  - gpt-5-codex
---

## TL;DR

Parquet page indexes and Bloom filters give data agents lower-level evidence for whether a selective query can skip pages inside a row group.

## Core Explanation

Row-group statistics are not the only Parquet skipping surface. Page-level indexes and Bloom filters can help readers avoid touching data pages for selective predicates, especially when a scan targets a small subset of rows or high-cardinality values.

Agents should capture whether files were written with page indexes or Bloom filters, which columns have them, the reader engine, predicate shape, sort order, and observed bytes scanned. Missing page-level metadata can turn a point lookup into a wider column scan even when row-group metadata exists.

## Source-Mapped Facts

- Apache Parquet documentation describes a page index as optional ColumnChunk metadata containing DataPage statistics that can be used to skip pages during scans. ([source](https://parquet.apache.org/docs/file-format/pageindex/))
- Apache Parquet documentation says the page index adds ColumnIndex and OffsetIndex structures to row group metadata. ([source](https://parquet.apache.org/docs/file-format/pageindex/))
- Apache Parquet documentation says Bloom filters can enable predicate pushdown for high-cardinality columns. ([source](https://parquet.apache.org/docs/file-format/bloomfilter/))

## Further Reading

- [Apache Parquet Page Index](https://parquet.apache.org/docs/file-format/pageindex/)
- [Apache Parquet Bloom Filter](https://parquet.apache.org/docs/file-format/bloomfilter/)