Info Commands

Inspect QPX datasets — view summaries, schemas, and Parquet metadata.

Overview

The info command group provides tools for inspecting QPX datasets. When invoked without a subcommand, it displays a summary of the dataset including available structures and row counts. Subcommands provide detailed schema and Parquet metadata inspection.

Available Commands

• info (default) - Show dataset summary with structures and row counts
• schema - Show Arrow schema for a data structure
• metadata - Show Parquet footer metadata

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info

Show a summary of a QPX dataset.

Parameters

Parameter	Type	Required	Default	Description
--dataset-path	DIRECTORY	No	-	Path to a QPX dataset directory
--verbose	FLAG	No	-	Enable verbose logging

Description

When invoked without a subcommand, displays a summary of the dataset including available structures and row counts. 

Usage Examples

Show dataset summary:

# Show dataset summary
qpxc info --dataset-path ./PXD014414

# Show schema for a specific structure
qpxc info schema --dataset-path ./PXD014414 --structure feature

# Show Parquet footer metadata
qpxc info metadata --file ./PXD014414/data.feature.parquet

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schema

Show the Arrow schema for a QPX data structure.

Description

Can read the schema from an on-disk Parquet file or display the canonical QPX schema as defined in code. 

Parameters

Parameter	Type	Required	Default	Description
--dataset-path	DIRECTORY	No	-	Path to a QPX dataset directory
--file	FILE	No	-	Path to a single Parquet file (alternative to --dataset-path)
--structure	CHOICE	No	-	QPX data structure name (when using --dataset-path)
--canonical	FLAG	No	-	Show the canonical QPX schema (from code) instead of the file schema
--verbose	FLAG	No	-	Enable verbose logging

Usage Examples

Inspect data structure schemas:

# Schema from a dataset structure
qpxc info schema --dataset-path ./PXD014414 --structure feature

# Schema from a standalone Parquet file
qpxc info schema --file ./data.feature.parquet

# Canonical QPX schema (from code)
qpxc info schema --structure feature --canonical

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metadata

Show Parquet footer metadata for QPX files.

Description

Displays the key-value metadata stored in the Parquet file footer, as well as basic file statistics (row groups, total rows, file size). 

Parameters

Parameter	Type	Required	Default	Description
--file	FILE	No	-	Path to a Parquet file
--dataset-path	DIRECTORY	No	-	Path to a QPX dataset directory (shows metadata for all files)
--verbose	FLAG	No	-	Enable verbose logging

Usage Examples

View Parquet file metadata:

# Single file
qpxc info metadata --file ./data.feature.parquet

# All files in a dataset
qpxc info metadata --dataset-path ./PXD014414

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Best Practices

• Use qpxc info to get a quick overview of a dataset before querying
• Use qpxc info schema --canonical to compare the on-disk schema against the QPX specification
• Use qpxc info metadata to check Parquet compression, row groups, and key-value metadata