There was a question here What is the difference between transaction cost and execution cost in remix?, but when I used Remix, I never see the transaction cost differing from execution cost here?
It's something like:
gas 3000000 gas
transaction cost 36846 gas
execution cost 36846 gas
when an exception happens, or
gas 86662 gas
transaction cost 75358 gas
execution cost 75358 gas
when the transaction executes without problems?
The transaction cost seems to always equal to the execution cost? And which number is the gas used? If the transaction is executed without problem, the gas number is the real gas used? But in case of an exception, the transaction cost is the gas used?