Blog de SQL Trainer

Artículos, guías y consejos sobre SQL

SQL JOIN for Beginners — Complete Guide

Complete guide to SQL JOINs: INNER, LEFT, RIGHT, FULL, CROSS. Examples with explanations, visual diagrams, common mistakes.

2026-03-0412 min de lectura
SQLJOINbeginners

SQL Window Functions — Examples and Explanations

Complete guide to SQL window functions: ROW_NUMBER, RANK, LAG, LEAD, SUM OVER. Practical examples for analytics.

2026-03-0415 min de lectura
SQLwindow functionsanalytics

Top 50 SQL Interview Queries You Must Know

Most popular SQL interview queries: from basic SELECT to complex window functions. Examples and explanations for your next interview.

2026-03-0418 min de lectura
SQLinterviewcareer

PostgreSQL vs MySQL — Which to Choose as a Developer

PostgreSQL vs MySQL comparison: performance, data types, JSON, window functions, replication. Pros and cons of each DBMS.

2026-03-0410 min de lectura
PostgreSQLMySQLcomparison

How to Prepare for a SQL Interview in 2 Weeks

Step-by-step SQL interview preparation plan: what to study, which problems to solve, how to ace the technical interview.

2026-03-048 min de lectura
SQLinterviewcareerpreparation