| Concept | Traditional Database | Solana Accounts |
|---|---|---|
| Data Location | Rows in tables on a centralized server | Accounts on a distributed ledger across validators |
| Schema | Defined by the database (SQL DDL, document schema) | Defined by the owning program; stored as raw bytes in the account's data field |
| Access Control | Application-level auth (SQL roles, app middleware) | Enforced by the runtime: only the owning program can modify an account, and only with the required signer(s) |
| Cost of Storage | Server/cloud hosting fees, pay for disk space | Rent-exempt deposit proportional to data size; refundable when the account is closed |
| Identity/Keys | Auto-increment IDs, UUIDs | 32-byte public keys or Program Derived Addresses (PDAs) |
| Reads | SQL queries, document lookups | RPC calls (getAccountInfo, getProgramAccounts) |
| Writes | INSERT/UPDATE via application code | Transactions with instructions, signed by authorized keys |
| Code vs Data | Application code and database are separate systems | Both are accounts; programs (code) and data accounts coexist in the same model |
| Deletion | DELETE query removes the row | Close the account, lamports are returned to you |
| Visibility | Private by default; you choose what to expose | Public by default; anyone can read any account's data |
Key Differences
1. Data Location
- Database: Data lives on centralized servers you control or pay someone to host
- Solana: Data is replicated across thousands of validator nodes worldwide
2. Access Control
- Database: Enforced by application logic and database permissions
- Solana: Enforced at the protocol level - a program cannot modify an account unless it owns it
3. Storage Costs
- Database: Monthly hosting fees for infrastructure
- Solana: Direct lamport deposit tied to each account - rent-exempt deposit for permanent storage
4. Querying
- Database: JOIN operations, server-side filtering, complex queries
- Solana: NO JOINS! Programs receive accounts as inputs. Off-chain queries via RPC, then client-side assembly
5. Transparency
- Database: Private by default, access controlled
- Solana: Public by default, anyone can read any account, anywhere, anytime
Web2 → Web3 Thinking
| Web2 | Web3 / Solana |
|---|---|
| Database row = unique record ID (auto-increment, UUID) | Solana account = unique public key (32 bytes) |
| Authentication = username + password | Authentication = secret key signature |
| Payment = monthly invoice | Payment = transaction fees (in lamports) |
| Data privacy = encryption + access control | Data privacy = cryptographic keys (account is public, but only signer can modify) |
| Backup = database replication | Backup = globally distributed ledger |
| Admin changes data | Program changes data (signed instruction) |
