DA

Automatically reviews SQL performance and data pipeline designs for optimization.

Install

mkdir -p .claude/skills/data-engineering-mazelb && curl -L -o skill.zip "https://agentskills.codes/api/skills/download/18186" && unzip -o skill.zip -d .claude/skills/data-engineering-mazelb && rm skill.zip

Installs to .claude/skills/data-engineering-mazelb

Activation

This is the description your AI agent reads to decide when to run this skill — the better it matches your request, the more reliably it fires.

Automatically reviews data pipelines, optimizes SQL queries, and ensures data quality. Activates when you mention: data pipeline, ETL, SQL optimization, query performance, data quality, schema design, Airflow DAG, database index, slow query. Provides: Pipeline design patterns, SQL query optimization, index recommendations, data validation strategies, schema improvements. Supports: PostgreSQL, MySQL, SQLAlchemy, Prisma, Spring Data JPA
438 chars✓ has a “when” triggerlonger than Claude Code's old 250-char listing cap (fine on current versions)
Intermediate

Key capabilities

  • Identify N+1 query problems, missing indexes, and inefficient JOINs in SQL queries.
  • Suggest best practices for idempotency, error handling, and monitoring in data pipeline design.
  • Check for schema validation, null handling, and duplicate detection to ensure data quality.
  • Optimize OpenSearch indexing and batch document processing for rag-project archetypes.
  • Recommend SQLAlchemy eager loading and connection pooling for api-service archetypes.

How it works

The skill activates upon detecting specific keywords or code related to data engineering, then analyzes the input to identify performance issues, design flaws, or quality concerns.

Inputs & outputs

You give it
SQL queries or database code, mentions of slow queries, discussions about data pipelines or ETL, questions about data quality, or work with database schema
You get back
Query analysis, execution plan, optimized query, index recommendations, and performance gains

When to use data-engineering

  • Optimizing slow SQL queries
  • Reviewing data pipeline performance
  • Improving database schema design

About this skill

Data Engineering Skill

Automatically optimizes data pipelines, SQL queries, and data quality.

When This Skill Activates

Claude invokes this skill when you:

  1. Show SQL queries or database code
  2. Mention slow queries or performance
  3. Discuss data pipelines or ETL
  4. Ask about data quality
  5. Work with database schema

What This Skill Does

1. SQL Query Optimization

Identifies:

  • N+1 query problems
  • Missing indexes
  • Inefficient JOINs
  • Unnecessary columns in SELECT
  • Lack of query limits

Example Optimization:

-- Before: Sequential scan (45ms)
SELECT * FROM users WHERE email = '[email protected]';

-- Add index
CREATE INDEX idx_users_email ON users(email);

-- After: Index scan (2ms) - 95% faster

2. Data Pipeline Design

Best Practices:

  • Idempotency (safe to rerun)
  • Error handling and retries
  • Monitoring and alerting
  • Data validation
  • Incremental processing

3. Data Quality

Checks for:

  • Schema validation
  • Null handling
  • Duplicate detection
  • Referential integrity
  • Data type consistency

Archetype-Specific Optimizations

For rag-project:

  • OpenSearch indexing optimization
  • Batch document processing
  • Embedding caching strategies
  • Vector search performance

For api-service:

  • Database query optimization
  • SQLAlchemy eager loading
  • Connection pooling
  • Query result caching

Output Format

Provides:

  1. Query Analysis: Performance issues
  2. Execution Plan: EXPLAIN output
  3. Optimized Query: Improved version
  4. Index Recommendations: SQL to create indexes
  5. Performance Gains: Expected improvements

Example Usage

User: "This query is slow: SELECT * FROM users JOIN profiles..."
Claude: [Activates data-engineering skill]
- Identifies N+1 problem
- Suggests eager loading
- Recommends indexes
- Provides optimized query

Result: 2000ms → 150ms (13x faster)

When not to use it

  • When the task does not involve SQL queries or database code.
  • When the discussion is not about data pipelines or ETL.
  • When the focus is not on data quality or schema design.

Limitations

  • The skill's support is limited to PostgreSQL, MySQL, SQLAlchemy, Prisma, and Spring Data JPA.
  • The skill focuses on specific archetypes like rag-project and api-service for specialized optimizations.

How it compares

This skill automatically provides specific optimizations and recommendations based on identified patterns, unlike a manual review that requires human expertise to diagnose and suggest improvements.

Compared to similar skills

data-engineering side by side with the closest alternatives in the catalog.

SkillInstallsUpdatedSafetyDifficulty
data-engineering (this skill)07moReviewIntermediate
find-hypertable-candidates13moNo flagsIntermediate
sql-queries184moNo flagsIntermediate
fuzzy-matching85moNo flagsAdvanced

Try saying

Example prompts that trigger this skill in your AI assistant.

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