validate-data

Validate schema and data quality after a dlt pipeline load.

Updated Jun 15, 2026
One-click install
npx skills add https://github.com/aminojagh/LLMZC --skill validate-data-aminojagh
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: validate-data
Source: https://github.com/aminojagh/LLMZC/tree/main/05_02_dlt_workshop/.claude/skills/validate-data
Command: npx skills add https://github.com/aminojagh/LLMZC --skill validate-data-aminojagh

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? After running a dlt pipeline, you often cannot tell whether the loaded tables have correct schemas, sensible data types, or properly flattened nested structures. This Skill inspects the loaded pipeline output and guides you through fixing type mismatches, nested arrays, and missing columns. ## Core Features & Use Cases - Schema Inspection: Export the pipeline schema as a Mermaid diagram showing tables, columns, types, and parent/child relationships. - Data Review: Open the Workspace Dashboard for visual browsing or query the data directly through the pipeline MCP server. - Iterative Fixes: Apply processing_steps (map, filter, yield_map), column type hints, and data_selector adjustments, then re-run in dev_mode until the schema is right. - Use Case: You loaded a REST API response and notice monetary amounts stored as floats and a nested results array. Use this Skill to convert amounts to Decimal, flatten the structure with yield_map, and verify the corrected schema. ## Quick Start Ask the assistant to validate the data loaded by your dlt pipeline and check whether the schema and column types look correct.

Frequently Asked Questions about validate-data

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I validate data after a dlt pipeline load?▼

Export the pipeline schema as a Mermaid diagram with dlthub local pipeline schema, then review tables and sample rows in the Workspace Dashboard or query them through the pipeline MCP server. Fix issues with processing_steps and re-run the pipeline.

How to fix wrong data types in dlt loaded tables?▼

Use processing_steps in the resource config with map, filter, or yield_map to transform items before loading. For monetary or precision-sensitive values, always convert to Decimal rather than float to avoid rounding errors.

Does dlt automatically flatten nested JSON structures?▼

dlt auto-unnests nested arrays into child tables named like <resource>__results, which works well for analytics. If you need a flat structure, use yield_map to flatten items or adjust data_selector to point deeper into the response.

Why are some columns missing after a dlt pipeline load?▼

Columns that are entirely null on the first load get no inferred type and may be absent. Add columns hints to the resource config with an explicit data_type, or adjust API parameters like group_by so the fields are populated.

How do I re-run a dlt pipeline after schema changes?▼

Enable dev_mode so each run produces a fresh dataset, then re-run the pipeline and inspect the result with the Mermaid schema export or MCP queries. Use the debug-pipeline skill to examine traces and load packages between iterations.