# Address Lookup Table Guide
This guide explains how to use Address Lookup Tables (ALT) in Sol Trade SDK to optimize transaction size and reduce fees.
## 📋 What are Address Lookup Tables?
Address Lookup Tables are a Solana feature that allows you to store frequently used addresses in a compact table format. Instead of including full 32-byte addresses in transactions, you can reference addresses by their index in the lookup table, significantly reducing transaction size and cost.
## 🚀 Core Benefits
- **Transaction Size Optimization**: Reduce transaction size by using address indices instead of full addresses
- **Cost Reduction**: Lower transaction fees due to reduced transaction size
- **Performance Improvement**: Faster transaction processing and validation
- **Network Efficiency**: Reduced bandwidth usage and block space consumption
## 🛠️ Implementation
Include lookup tables in your trade parameters:
```rust
let lookup_table_key = Pubkey::from_str("use_your_lookup_table_key_here").unwrap();
let address_lookup_table_account = fetch_address_lookup_table_account(&client.rpc, &lookup_table_key).await.ok();
// Include lookup table in trade parameters
let buy_params = sol_trade_sdk::TradeBuyParams {
dex_type: DexType::PumpFun,
mint: mint_pubkey,
sol_amount: buy_sol_amount,
slippage_basis_points: Some(100),
recent_blockhash: Some(recent_blockhash),
extension_params: Box::new(PumpFunParams::from_trade(&trade_info, None)),
address_lookup_table_account: address_lookup_table_account, // Include lookup table
wait_transaction_confirmed: true,
create_wsol_ata: false,
close_wsol_ata: false,
create_mint_ata: true,
open_seed_optimize: false,
};
// Execute transaction
client.buy(buy_params).await?;
```
## 📊 Performance Comparison
| **Transaction Size** | ~1,232 bytes | ~800 bytes | 35% reduction |
| **Address Storage** | 32 bytes per address | 1 byte per address | 97% reduction |
| **Transaction Fees** | Higher | Lower | Up to 30% savings |
| **Block Space Usage** | More | Less | Improved network efficiency |
## ⚠️ Important Notes
1. **Lookup Table Address**: Must provide a valid address lookup table address
3. **RPC Compatibility**: Ensure your RPC provider supports lookup tables
4. **Network Specific**: Lookup tables are network-specific (mainnet/devnet/testnet)
5. **Testing**: Always test on devnet before using on mainnet
## 🔗 Related Documentation
- [Trading Parameters Reference](TRADING_PARAMETERS.md)
- [Example: Address Lookup Table](../examples/address_lookup/)
## 📚 External Resources
- [Solana Address Lookup Tables Documentation](https://docs.solana.com/developing/lookup-tables)