Enhanced QueryBuilder Usage Guide

This guide demonstrates how to use the enhanced QueryBuilder system with practical examples showcasing all the modern features, safety enhancements, and best practices.

🚀 Getting Started

<?php
use Gemvc\Database\QueryBuilder;

// Create a new QueryBuilder instance
$queryBuilder = new QueryBuilder();

📖 Table of Contents

• SELECT Queries
• INSERT Queries
• UPDATE Queries
• DELETE Queries
• Enhanced WHERE Conditions
• Pagination & Limiting
• Error Handling
• Transactions
• Integration with Table Classes
• Best Practices

SELECT Queries

Basic SELECT

$users = $queryBuilder->select('id', 'name', 'email')
    ->from('users')
    ->run();

if ($users === null) {
    echo "Error: " . $queryBuilder->getError();
} else {
    foreach ($users as $user) {
        echo "User: " . $user['name'] . "\n";
    }
}

SELECT with Aliases and JOINs

$userPosts = $queryBuilder->select('u.name', 'p.title', 'p.created_at')
    ->from('users', 'u')
    ->leftJoin('posts p ON u.id = p.user_id')
    ->whereEqual('u.status', 'active')
    ->orderBy('p.created_at', true) // DESC
    ->run();

SELECT with Complex Conditions

$products = $queryBuilder->select('*')
    ->from('products')
    ->whereEqual('category', 'electronics')
    ->whereBetween('price', 100, 500)
    ->whereIn('brand', ['apple', 'samsung', 'google'])
    ->whereNotNull('description')
    ->orderBy('price')
    ->limit(20)
    ->run();

Get JSON Results

$jsonData = $queryBuilder->select('id', 'name', 'email')
    ->from('users')
    ->whereEqual('status', 'active')
    ->json();

if ($jsonData === null) {
    echo "Error: " . $queryBuilder->getError();
} else {
    echo $jsonData; // JSON string ready for API response
}