| Mechanism | Usefulness wrt data complexity | Search capabilities | Ease of use | Standards | Example |
|---|---|---|---|---|---|
| Files | Low: yes High: no |
Sequential | Easy to get started | Basics: yes Details: no |
Any (flat) file |
| Keyword/value databases | Low: yes High: no |
Random access | Easy to get started | De facto | DBM, Berkeley DB, GDBM |
| Relational databases | Low: overkill High: yes |
Random access, complex queries | Difficult setup, administration | SQL92 (kind of) standard | MySQL, PostgreSQL, Oracle, Sybase |
| Object-oriented databases | Low: overkill High: yes |
Random access, follow references | Depends on language and system | No: a mess | AceDB, ZODB |