21-query-profiling

Query Performance Profiling Examples

This directory contains examples demonstrating the Query Performance Profiler feature.

Overview

The Query Performance Profiler tracks query execution times, memory usage, and identifies slow queries to help you optimize database performance.

Files

• 01-profiling-examples.php - Basic profiling usage examples

Running Examples

Basic Usage

# Using SQLite (default)
php examples/21-query-profiling/01-profiling-examples.php

# Using MySQL
PDODB_DRIVER=mysql \
  DB_HOST=localhost \
  DB_NAME=testdb \
  DB_USER=testuser \
  DB_PASS=testpass \
  php examples/21-query-profiling/01-profiling-examples.php

# Using PostgreSQL
PDODB_DRIVER=pgsql \
  DB_HOST=localhost \
  DB_NAME=testdb \
  DB_USER=testuser \
  DB_PASS=testpass \
  php examples/21-query-profiling/01-profiling-examples.php

Example Output

=== Query Performance Profiling Examples ===

Driver: sqlite

1. Basic Profiling Setup
   --------------------
Enable profiling with slow query threshold of 0.1 seconds:
   ✓ Profiling enabled

2. Inserting Test Data
   --------------------
   ✓ Inserted 50 test records

3. Executing Queries
   --------------------
   ✓ Executed multiple queries

4. Profiling Statistics
   --------------------
Aggregated Statistics:
  Total queries: 12
  Total execution time: 15.23 ms
  Average execution time: 1.27 ms
  Min execution time: 0.45 ms
  Max execution time: 8.90 ms
  ...

Features Demonstrated

1. Enabling/Disabling Profiling - Control when profiling is active
2. Slow Query Detection - Automatic detection of queries exceeding threshold
3. Aggregated Statistics - Overall performance metrics across all queries
4. Per-Query Statistics - Detailed metrics for each unique query pattern
5. Slowest Queries - Identification of performance bottlenecks
6. Memory Tracking - Memory consumption per query
7. Profiler Reset - Clearing statistics for new measurement periods

See Also

• Query Profiling Documentation
• Performance Optimization Guide