Solana Transactions: not just a “request/response” ,but “atomic on-chain state changes”

In web2 , our rest api call are confined with just request and response framework . In web3 , for this particular solana , our transaction goes through this full commitment lifecycle:

send() → Processed ✓ → Confirmed ✓ → Finalized ✓

State	What it means
Processed	Validator received the transaction
Confirmed	2/3 of stake weight agrees
Finalized	Permanent — cannot be rolled back

sendAndConfirmTransaction() polls internally through all 3 states and resolves once finalized.

Pay to attempt, not just to succeed

Unlike of web2 , on which failed transaction incur nothing ,in web3 , we pay to attempt, not just to succeed. The chain ran the instruction, hit the error, and charged the fee anyway.

During my day 19 of 100 days of solona , I revealed:

Status: Error processing Instruction 0 — custom program error: 0x1

0x1 = InsufficientFunds on the System Program

What the failed tx showed

Field	Value from my terminal
Error code	`custom program error: 0x1`
Fee charged	`0.000005 SOL` (still deducted)
Compute Units	`150` consumed
Balance change	`1.468975 → 1.46897` (fee only)
Log message	`Transfer: insufficient lamports 1468970000, need 500000000000`

Final Note : err.logs vs console.error

	`err.logs`	`console.error(err)`
Source	Solana runtime (on-chain)	Node.js
Tells you	WHY the chain rejected it	WHERE your code broke
Can be undefined?	Yes — if tx never reached the chain	No — always present
Example	`Transfer: insufficient lamports…`	`SendTransactionError: simulation failed…`

Recommendation : Always use both:

} catch (err) {
  console.error("JS error:", err.message);     // WHERE it broke
  if (err.logs) {
    console.log("Chain logs:", err.logs);       // WHY chain rejected
  }
}