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data

Practical resources about data for software engineers.

87 results

Understanding Data Processing in Software Engineering

Every application eventually deals with data — parsing user input, serializing objects for APIs, validating form submissions, or transforming records between formats. Getting data handling right is what separates fragile scripts from production-grade systems.

This collection covers practical recipes and patterns for working with JSON, CSV, XML, YAML, and custom formats. You will find copy-paste solutions for common tasks like flattening nested objects, sanitizing user input, generating slugs, and formatting dates across Python, Java, and JavaScript.

intermediate

Batch Processing Patterns

Design reliable batch processing pipelines for large datasets with retry logic, idempotency, and observability.

intermediate

Caching & Memoization

How to cache expensive computations and API responses using in-memory, LRU, and distributed caches across Python, JavaScript, and Java.

beginner

Convert CSV to JSON

How to convert CSV data to JSON format in Python, Java, and JavaScript.

beginner

Convert JSON to CSV

How to convert JSON data to CSV format in Python, Java, and JavaScript.

beginner

Validate and Sanitize User Input Data

How to validate, sanitize, and constrain user input data at the application boundary using schemas, type checking, and validation libraries.

beginner

Date Formatting

How to parse, format, and manipulate dates across timezones using Python, JavaScript, and Java.

intermediate

Deep Clone Objects in JavaScript

How to create deep copies of JavaScript objects and arrays correctly, handling circular references, Dates, Maps, Sets, and custom classes.

beginner

Deep Clone Objects in JavaScript: Beyond JSON.parse

Compare deep clone strategies including JSON.parse, structuredClone, manual recursion, and library approaches for copying nested objects with circular references and special types

beginner

Diff JSON Objects

How to compare two JSON objects and find differences in Python, Java, and JavaScript.

intermediate

Flatten and Unflatten Nested Objects

How to convert nested objects to flat key-value pairs and back again, with dot-notation, bracket notation, and custom separator support.

beginner

Format Phone Numbers

How to format and validate phone numbers in Python, Java, and JavaScript.

intermediate

Generate PDF Reports with Python

Create styled PDF documents from data using ReportLab and fpdf2 in Python.

beginner

Generate URL Slugs

How to generate clean, URL-friendly slugs from strings in multiple programming languages.

beginner

Merge JSON Files

How to merge multiple JSON files into a single object or array in Python, Java, and JavaScript.

intermediate

Merge JSON Files in JavaScript

Combine multiple JSON files with conflict resolution strategies using Node.js.

intermediate

Money and Currency Handling

How to represent, parse, format, and calculate monetary values accurately across currencies.

beginner

Parse Command Line Arguments

How to parse command line arguments in Python, Java, and Node.js CLI applications.

beginner

Parse CSV Files

How to parse CSV files in Python, Java, and JavaScript with practical code examples.

beginner

Parse CSV Files with Python and Pandas

How to read, filter, and transform large CSV files efficiently using Python pandas and the csv module.

beginner

Parse Excel Files

How to read and write Excel (.xlsx) files in Python, Java, and JavaScript.

beginner

Parse JSON

How to parse JSON strings into native data structures across multiple programming languages.

intermediate

Parse Log Files

How to parse and analyze server log files using Python, Java, and JavaScript.

beginner

Parse Markdown Files

How to parse Markdown to HTML and extract structured data in Python, Java, and JavaScript.

beginner

Parse PDF Files

How to extract text and metadata from PDF files in Python, Java, and JavaScript.

beginner

Parse TOML Files

How to parse TOML configuration files in Python, Java, and JavaScript.

beginner

Parse XML Files

How to parse XML documents in Python, Java, and JavaScript with practical code examples.

beginner

Parse YAML Files

How to parse YAML configuration files in Python, Java, and JavaScript.

advanced

Schedule and Monitor DAGs with Apache Airflow

How to define, schedule, and monitor Directed Acyclic Graphs in Apache Airflow with operators, sensors, XCom, and task dependencies.

advanced

Parallel DataFrame Operations with Dask

How to use Dask for parallel DataFrame operations on datasets larger than memory, covering lazy evaluation, partitions, custom computations, and distributed scheduling.

intermediate

Validate DataFrame Schemas with Pandera

How to validate pandas and Polars DataFrame schemas with Pandera, covering column types, constraints, custom checks, hypothesis testing, and schema inheritance.

intermediate

Transform Data in the Warehouse with dbt

How to use dbt for SQL-based data transformations with models, tests, materializations, macros, and incremental loading in a data warehouse.

intermediate

Read and Write Excel Files with Python

How to read, write, and format Excel spreadsheets using openpyxl and pandas in Python.

beginner

Generate QR Codes with Python

Create QR codes for URLs, text, and contact cards using the qrcode library in Python.

intermediate

Build an ETL Pipeline with pandas and Parquet

How to build an extract-transform-load pipeline using pandas for data processing and Parquet for columnar storage with type coercion and validation.

intermediate

High-Performance DataFrame Operations with Polars

How to use Polars for fast DataFrame operations with lazy evaluation, expression API, streaming, and interop with pandas for large datasets.

advanced

Large-Scale Aggregation with PySpark

How to perform group-by aggregations on large datasets with PySpark, covering window functions, UDFs, broadcast joins, and performance tuning.

intermediate

Extract Data from HTML Pages with Python and BeautifulSoup

Parse HTML and extract data using BeautifulSoup. Covers CSS selectors, navigation, tables, pagination, and respectful scraping with rate limiting.

beginner

Regular Expressions

How to use regular expressions for pattern matching, validation, and text extraction across Python, JavaScript, and Java.

beginner

Serialize and Deserialize Data

How to serialize and deserialize data in JSON, XML, and YAML across Python, Java, and JavaScript.

beginner

Sort an Array

How to sort arrays and lists in ascending, descending, and custom order across multiple languages.

advanced

Recursive CTEs for Hierarchical Data Queries

How to query hierarchical data with recursive Common Table Expressions in SQL, covering tree traversal, org charts, category trees, and cycle detection.

beginner

Truncate Text

How to truncate text with ellipsis and word boundaries in Python, Java, and JavaScript.

beginner

URL Encoding

How to encode and decode URLs, query parameters, and path segments safely across Python, JavaScript, and Java.

beginner

URL Encoding and Decoding

Master URL encoding in JavaScript and other languages with encodeURI, encodeURIComponent, plus-safe handling, RFC 3986 compliance, and decoding edge cases

beginner

UUID Generation

How to generate universally unique identifiers (UUIDs) for database keys, session tokens, and resource naming across Python, JavaScript, and Java.

beginner

UUID Generation: v4, v7, and ULID Comparison

Compare UUID v4, v7, ULID, and nanoid for generating unique identifiers with different tradeoffs in randomness, sortability, performance, and database index locality

intermediate

Validate JSON Schema

How to validate JSON data against schemas in Python, Java, and JavaScript.

intermediate

Implement ACID Transactions in PostgreSQL

How to use PostgreSQL transactions to ensure Atomicity, Consistency, Isolation, and Durability for reliable multi-step database operations

intermediate

Elasticsearch Aggregations for Analytics and Search

How to use Elasticsearch aggregations to build faceted search, analytics dashboards, and real-time metrics from indexed data

beginner

Build Responsive Email Templates with MJML

Create cross-client responsive email templates using MJML markup, live Handlebars variables, and inline CSS for reliable rendering across Gmail, Outlook, and Apple Mail

intermediate

RAG Hybrid Search Pattern

Combine keyword (BM25) and semantic (vector) search to improve retrieval accuracy in RAG pipelines. Fuse ranked results using reciprocal rank fusion.

advanced

Batch-to-Streaming Bridge

How to bridge batch and streaming pipelines with a data lake. Covers Lambda architecture, Kafka Connect S3 sink, schema alignment, and unified serving layer.

advanced

CDC Pattern: Stream Database Changes to Downstream

How to stream database changes to downstream consumers with CDC. Covers log-based CDC, Debezium, Kafka Connect, outbox pattern, and consumer reconciliation.

advanced

Data Lineage Tracking: Track Origin End-to-End

How to track data origin and transformations end-to-end. Covers column-level lineage, OpenLineage, Marquez, metadata injection, and impact analysis.

intermediate

ETL Extract-Transform-Load

How to build ETL pipelines with extract, transform, and load stages. Covers staging tables, incremental extraction, idempotent loads, and orchestration.

intermediate

Idempotent Load: Re-run Data Loads Safely Without Duplicates

How to re-run data loads safely without duplicates. Covers deduplication keys, MERGE upserts, load IDs, partition overwrite, and transactional loads.

advanced

Schema Registry Evolution

How to manage schema versions for streaming pipelines with a schema registry. Covers Avro, backward compatibility, forward compatibility, and consumer migration.

advanced

Data Migration Runbook Template

A runbook template for safely migrating data between systems including pre-migration checks, rollback procedures, and post-migration validation.

advanced

Complete Guide to Kafka Stream Processing

Build real-time event streaming pipelines with Kafka. Covers producers, consumers, Kafka Streams, Kafka Connect, schema registry, and stream processing patterns.

intermediate

Data Lake vs Data Warehouse — Architecture Guide

A practical guide to Data Lake architecture: structured vs unstructured storage, lakehouse concepts, ETL vs ELT patterns, and when to choose a lake over a warehouse.

advanced

Data Mesh Architecture — Decentralized Data Ownership

A practical guide to Data Mesh: decentralizing data ownership to domain teams, treating data as a product, and enabling self-serve data infrastructure.

intermediate

Lakehouse Architecture — The Best of Both Worlds

A practical guide to Lakehouse architecture: combining data lake storage flexibility with data warehouse reliability using open table formats like Delta Lake, Apache Iceberg, and Hudi.

intermediate

Blob Storage: S3, GCS, and Azure Blob Patterns for Engineers

A practical guide to cloud blob storage: bucket design, access control, lifecycle policies, multipart uploads, presigned URLs, and cost optimization patterns for S3, Google Cloud Storage, and Azure Blob.

intermediate

Caching Strategies: From Browser to Database, a Complete

A practical guide to caching strategies: browser caching, CDN edge caching, application caching with Redis, and database query caching. Learn when to use each and how to avoid cache invalidation nightmares.

advanced

Apache Airflow: DAGs, Operators, Scheduling

Master Apache Airflow: DAGs, operators, sensors, XCom, scheduling, backfilling, connections, variables, and production patterns for data pipeline orchestration.

advanced

Data Pipeline Architecture: Batch, Streaming, Lambda, Kappa

Master data pipeline architecture: batch processing, streaming, lambda and kappa patterns, ETL vs ELT, and choosing the right approach for your data workloads.

advanced

Data Quality Guide: Validation, Profiling, Great

Master data quality: validation frameworks, profiling, schema enforcement, anomaly detection, and monitoring with Great Expectations, Pandera, and Soda for reliable pipelines.

advanced

dbt: Models, Tests, Macros, Materializations

Master dbt for data transformations: models, tests, macros, materializations, seeds, snapshots, Jinja templating, and production patterns for analytics engineering.

advanced

Data Migration: Zero-Downtime Strategies That Work

A practical guide to data migration: planning, dual-write patterns, backfill strategies, schema evolution, validation, and rollback procedures for moving data without service interruption.

intermediate

ETL Pipelines: Extract, Transform, Load for Data Engineers

A practical guide to ETL pipelines: extracting data from multiple sources, transforming with validation and business logic, and loading into data warehouses. Covers batch scheduling, error handling, and monitoring with Python, dbt, and Airflow.

intermediate

Full-Text Search — Implement Search That Actually Works

A practical guide to full-text search: PostgreSQL tsvector, Elasticsearch indexing, query design, relevance tuning, and building search that users trust with autocomplete, faceting, and typo tolerance.

advanced

Real-Time Analytics: From Events to Dashboards in Seconds

A practical guide to real-time analytics: event collection, stream processing, data warehousing, and building sub-second dashboards with Kafka, ClickHouse, Druid, and modern OLAP databases.

advanced

Stream Processing: Event-Driven Data Pipelines with

A practical guide to stream processing: choosing between Kafka Streams, Flink, and Spark Streaming, designing event schemas, handling stateful operations, and building exactly-once processing pipelines for real-time data.

advanced

Complete Guide to Elasticsearch Cluster Setup

Deploy and scale Elasticsearch clusters. Covers node roles, sharding, replicas, index templates, mapping, snapshots, and production tuning for search at scale.

advanced

Complete Guide to SQL Query Optimization

Optimize SQL queries. Covers EXPLAIN plan analysis, index strategies, join optimization, N+1 query detection, query rewriting, materialized views, partitioning, connection pooling, and query caching with practical PostgreSQL and MySQL examples.

intermediate

Graph Databases — Neo4j and Property Graph Modeling

A practical guide to graph databases: property graph model, Cypher query language, modeling patterns, and when to choose Neo4j over relational databases.

intermediate

NoSQL Data Modeling Patterns

A practical guide to NoSQL data modeling: embedding vs referencing, access pattern-driven design, and patterns for MongoDB, DynamoDB, Cassandra, and Redis.

intermediate

SQL CTEs — Common Table Expressions Explained

A practical guide to SQL Common Table Expressions (CTEs): non-recursive and recursive CTEs, readability, performance, and when to use them over subqueries.

beginner

SQL Joins — Visual Guide with Examples

A visual guide to SQL joins: INNER, LEFT, RIGHT, FULL OUTER, CROSS, and SELF joins with practical examples, performance tips, and common pitfalls.

intermediate

SQL Window Functions — Complete Guide

A practical guide to SQL window functions: ROW_NUMBER, RANK, DENSE_RANK, LEAD, LAG, SUM, AVG over partitions, and real-world analytics use cases.

intermediate

Vector Databases — AI/ML Embeddings and Similarity Search

A practical guide to vector databases: embeddings, similarity search, approximate nearest neighbors, and choosing between Pinecone, Weaviate, pgvector, and Chroma.

intermediate

A/B Testing: Experimentation Frameworks for Data-Driven

A practical guide to A/B testing: experiment design, statistical significance, sample sizing, avoiding pitfalls, and building an experimentation culture in engineering teams.

beginner

AWS Basics — Core Services for Developers

A practical guide to AWS core services for developers: compute, storage, databases, networking, and security fundamentals with hands-on examples.

beginner

Azure Basics — Core Services for Developers

A practical guide to Microsoft Azure core services for developers: compute, storage, databases, networking, and identity with hands-on examples.

beginner

GCP Basics: Core Services for Developers

A practical guide to Google Cloud Platform core services for developers: compute, storage, databases, networking, and data analytics with hands-on examples.

intermediate

Terraform Best Practices — Modules, State, and Workspaces

A practical guide to Terraform best practices: module design, remote state management, workspaces, and security for production-grade infrastructure as code.

intermediate

GDPR Compliance — A Practical Guide for Developers

A developer-focused guide to GDPR compliance: data subject rights, lawful basis, data minimization, and technical measures for privacy by design.