Honest limitations.
WHAT THEY DO POORLY
Storing large data High-throughput processing Anything requiring correction Anything requiring privacy by default Anything requiring speed
WHY STORAGE SPECIFICALLY
Every node stores everything, forever, which makes it extraordinarily expensive per byte.
WHAT TO DO INSTEAD
Store a fingerprint on the ledger and the data elsewhere.
WHAT THE ORACLE PROBLEM IS
A blockchain cannot know anything about the outside world.
WHY THAT MATTERS ENORMOUSLY
Any application depending on external facts depends on whoever supplies them.
WHAT THAT MEANS
The trustlessness claimed stops at the boundary.
WHAT AN EXAMPLE LOOKS LIKE
A contract paying out on a delivery requires someone to assert the delivery occurred.
WHAT THAT PERSON IS
A trusted party, reintroduced.
WHAT IMMUTABILITY COSTS
Errors cannot be corrected, and neither can defects in deployed code.
WHAT REGULATION FREQUENTLY REQUIRES
Data correction and erasure, which immutability prevents.
WHAT TO CONSIDER
Whether that conflict is resolvable for your use.
WHAT TO BE SCEPTICAL OF
Proposals where a database and an agreement would work identically.
WHAT THAT DESCRIBES
Most proposals.
