알면 좋은 RDBMS 구조 키워드

키워드 분류

기본

1. 객체: Table, Index(B tree), View, Material View, Procedure, Function, Trigger, Sequence(+SCN), Synonym 등
2. Statement: DML, DDL, TCL, DCL
3. row type: NUMBER, VARCHAR2, NVARCHAR2, CLOB, NCLOB, BLOB
4. Data Dictionary View: ALL_TABLES, ALL_USERS, DBA_TABLES, DBA_SEGMENTS, USER_CONSTRAINTS, V$SESSION 등
5. DD(System Tables): 4번 DD View의 code를 조회하면 실제 테이블 이름이 나온다. tibero는 SYS._DD_TBL과 같은 이름이다.
6. LOB segment

physical structure(file, disk)

1. Database instance - Tablespace - Segment - Extent - Datablock - OS block
2. Datafile / Controlfile
3. Row Chaining, Row Migration, Chained Row Pieces
4. Redo Log
5. Undo Tablespace, ITL

logical structure(memory)

1. SGA / PGA
2. Buffer Cache, Large Pool
3. Redo Log Buffer, undo retention

동작 방식

1. DB instance 상태 (SHUTDOWN, NOMOUNT, MOUNT, OPEN)
2. DB instance 종료 (NORMAL, TRANSACTIONAL, IMMEDIATE, ABORT)
3. tx isolation level, ACID property
4. DML lock, DDL lock (row lock, table lock // RS, RX, S, SRX, X)
5. high water mark(HWM)

recovery

1. instance recovery, media recovery
2. roll forward, roll back
3. incarnation number