Bits of .NET

🔍 Query Plan = Performance Tuning

Yavaş sorguları hızlandırın. PostgreSQL Query Plan ile sorgu performansını analiz edin.

🎯 Query Plan Analizi

# 1. EXPLAIN ANALYZE
EXPLAIN (ANALYZE, BUFFERS, COSTS) 
SELECT * FROM orders WHERE customer_id = 12345;

# 2. Plan Operations
- Seq Scan: Full table scan (expensive)
- Index Scan: Using index (fast)
- Index Only Scan: Data from index (fastest)
- Hash Join: Memory intensive
- Merge Join: Sorted data
- Nested Loop: Small datasets

# 3. Identifying Issues
# High cost operations
# Large row counts
# Buffer hits/misses
# Sort operations
# Temporary files

# 4. Optimization
CREATE INDEX idx_orders_customer_date 
    ON orders (customer_id, order_date);

# 5. Analyze Tables
ANALYZE orders;
ANALYZE customers;

# 6. Monitoring Tools
pg_stat_statements
pg_stat_user_tables
pg_stat_user_indexes

✅ Query Plan Optimization

• ✓ Index usage kontrolü
• ✓ Join stratejileri
• ✓ Buffer hit ratio
• ✓ Work_mem ayarları
• ✓ Query rewriting