Merge & Aggregate in n8n
From the n8n cheat sheet · Essential Nodes · verified Jul 2026
Merge & Aggregate
Combine data from multiple sources
yaml
# Merge Node Modes
- Append: Combine all items into one list
- Merge By Fields: Join by matching key (like SQL JOIN)
- Merge By Position: Combine by array index
- Multiplex: Cartesian product
- SQL Query: Custom SQL (v1.49.0+)
# Aggregate Node
Operation: Aggregate Individual Fields
Fields: items (creates array from all items)⚠️ Merge node can execute BOTH IF branches even if one is empty
💡 Use "Merge By Fields" for SQL-like joins
📌 Aggregate is opposite of Split Out (items → array)
⚡ SQL Query mode (v1.49.0+) enables custom join logic