1Z0-182 Exam Questions & Answers

A .False. Works with DMTs too.

B .True. LMTs use bitmaps, unlike DMT freelists.

C .False. OMF is independent of management type.

D .False. Alerts work with both.

E .True. Shrink requires LMTs with ASSM.

A . REDO is used for read consistency.False. Read consistency is achieved using UNDO, which provides a consistent view of data as of a specific point in time. REDO logs changes for recovery, not consistency.

B . UNDO is used for some flashback operations.True. Flashback features like Flashback Query and Flashback Table rely on UNDO to reconstruct past states of data.

C . UNDO is used for read consistency.True. UNDO stores pre-change data, enabling multi-version read consistency for queries.

D . Both REDO and UNDO can be multiplexed.False. REDO logs can be multiplexed (mirrored across multiple destinations), but UNDO is managed within a single UNDO tablespace per instance (though it can have multiple data files).

E . REDO is used for ROLLBACK.False. ROLLBACK uses UNDO to revert changes; REDO logs the changes but isn't used to undo them.

F . REDO is used for instance recovery.True. REDO logs are replayed during instance recovery to reapply committed changes after a crash.

A .True. CREATE SPFILE FROM PFILE works when idle.

B .False. Includes dynamic parameters too.

C .True. CREATE PFILE FROM SPFILE generates a PFILE.

D .False. A PFILE can start the instance if no SPFILE exists.

E .True. Dynamic parameters (e.g., DB_CACHE_SIZE) are modifiable.

A .True. PDB_DBA grants admin rights (e.g., CREATE SESSION, ALTER SYSTEM) within the PDB.

B .False. DDL on objects requires ownership or explicit grants.

C .False. User management needs CREATE USER privilege, not inherent.

D .False. It includes multiple privileges, not none.

Logical structures (e.g., segments, extents) map to physical structures (e.g., data files, blocks). Let's dissect each option:

A . A segment can span multiple data files in some tablespaces.

True. A segment (e.g., a table or index) is a logical entity stored in a tablespace. In a smallfile tablespace (default in Oracle), a segment's extents can span multiple data files if the tablespace has multiple files and space allocation requires it. This is common in large tables or when autoextend adds new files.

Mechanics:Oracle allocates extents across available data files in a round-robin fashion (with ASSM) or as needed, ensuring the segment's data is distributed. This doesn't apply to bigfile tablespaces, which use a single data file.

Example:A 10GB table in a tablespace with two 5GB data files will span both.

B . Segments can span multiple tablespaces.

False. A segment is confined to a single tablespace. Oracle enforces this to maintain logical separation (e.g., a table's data stays in its assigned tablespace). Partitioned tables can have partitions in different tablespaces, but each partition is a separate segment.

Why Not:The segment header and extent map reside in one tablespace, preventing cross-tablespace spanning for a single segment.

C . A segment might have only one extent.

True. A segment starts with one extent upon creation (e.g., a small table or index). If no further growth occurs, it remains a single-extent segment. This is common with small objects or when INITIAL extent size suffices.

Mechanics:In locally managed tablespaces (default), the initial extent is allocated based on INITIAL or tablespace defaults (e.g., 64KB), and additional extents are added only as needed.

D . All tablespaces may have one or more data files.

False. Bigfile tablespaces are restricted to one data file (up to 128TB). Smallfile tablespaces (traditional) can have multiple data files (up to 1022), but the ''all'' phrasing makes this false due to bigfile exceptions.

Clarification:The question's intent may assume smallfile tablespaces, but Oracle 23ai supports both types.