Lesson 2 — Vocabulary, Controlled Change, and Administrator Roles
Database object vocabulary
| Term | Source-bound meaning | Fast clue |
|---|---|---|
| Database | collection of stored data, regardless of structure/content | the stored collection |
| Instance | running execution of database software controlling access to storage | running DBMS context |
| Schema | organized subset/collection of database objects, often with owner/access list | object container |
| Node | individual computer participating in a distributed database | one distributed computer |
| Database abstraction | common interface/API across databases | portability, but product-specific functions may be hidden |
Do not collapse database and instance. The first is the stored collection; the second is the executing software context.
Lifecycle and controlled change
Lifecycle responsibilities include acquisition, migration, retention, expiration, and disposition. Chapter 6 describes the DBA as custodian of database changes: many parties may request a change, but database changes must be defined precisely, implemented controllably, and kept auditable.
Production change should have:
- documented/approved request;
- lower-environment testing;
- repeatable script/process;
- audit trail;
- tested back-out plan;
- configuration status aligned to approved design.
A direct console update to thousands of Production rows is risky even if the SQL is syntactically correct: it may not be reproducible, reviewable, testable, traceable, or safely reversible.
Administrator roles
| Role | Primary focus | Stem clues |
|---|---|---|
| Production DBA | production reliability, monitoring, performance, backup/recovery, failover, archiving, maintenance, capacity | Production, SLA, outage, tuning, recovery |
| Application DBA | one or more application databases across Development/Test/QA/Production | application-specific DBs; close developer/support-team work |
| Procedural DBA | DBMS procedural logic | stored procedures, triggers, UDFs |
| Development DBA | design and special-use/development databases | design, sandbox, exploratory DB |
| NSA | hardware/software supporting storage arrays | SAN/storage-array infrastructure |
Roles may be combined in real organizations. The exam tests the responsibility, not an org-chart mandate.
Changed-fact drill
Failover + backup/recovery + Production availability → Production DBA. Change the stem to one application's databases across dev/test/prod → Application DBA.
Source: pp. 169–171.