Oracle Database 1z0-182 Exam Questions and Answers PDF

Background processes manage core database operations. Let’s break it down:

A. Creating dedicated server connections.

Explanation:False. Dedicated server connections are created by the listener, not background processes. The listener hands off the connection to a server process (e.g., ora_s000), which isn’t a background process.

B. Registering services with Oracle Net listeners.

Explanation:True. The LREG process (Listener Registration, formerly PMON’s role) registers services with listeners, using parameters like LOCAL_LISTENER.

Mechanics:LREG sends service details (e.g., orcl) to the listener every 60 seconds or on startup.

C. Writing redo to log files.

Explanation:True. The LGWR (Log Writer) process writes redo entries from the redo log buffer to online redo log files, ensuring transaction durability.

Mechanics:Triggered by commits, log buffer fills, or checkpoints.

D. Writing dirty database block images from the buffer cache.

Explanation:True. The DBWn (Database Writer) processes write modified (dirty) blocks from the buffer cache to data files, maintaining consistency.

Mechanics:Occurs at checkpoints or when free buffers are needed.

E. Reading database blocks into the buffer cache.

Explanation:False. Server processes (foreground) read blocks into the buffer cache during user queries, not background processes.

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.True. TIMED_STATISTICS = FALSE disables timing data collection.

B.False. No such procedure exists.

C.False. No TIMED_STATISTICS_LEVEL parameter exists.

D.True. STATISTICS_LEVEL = BASIC disables most performance monitoring.

E.False. No such procedure exists.

SQL*Loader (sqlldr) loads data from external files into Oracle tables. The command sqlldr u1/oracle TABLE=emp uses defaults since no control file is specified. Let’s evaluate:

A. It overwrites the data for Alan and adds data for Curl and Bob.

Explanation:False. SQLLoader’s default mode is APPEND, not REPLACE. It doesn’t “overwrite” existing rows unless REPLACE or TRUNCATE is specified in a control file. Here, row 1, Alan, 2 exists, and SQLLoader will either skip it (if a primary key rejects duplicates) or raise an error, but it won’t overwrite. 3, Curl, 4 and 4, Bob, 4 are appended.

Mechanics:Without a control file, SQL*Loader assumes APPEND and matches columns positionally (ENO, ENAME, DN).

B. It generates a log that contains control file entries, which can be used with normal SQL*Loader operations.

Explanation:True. SQL*Loader always generates a log file (e.g., emp.log) when invoked. With no control file specified, it auto-generates one internally and logs it, including entries like LOAD DATA INFILE 'emp.dat' APPEND INTO TABLE emp FIELDS TERMINATED BY ',' (ENO, ENAME, DN). This can be reused.

Practical Use:The log’s control section is editable for future runs (e.g., changing to REPLACE).

C. It appends data from EMP.DAT to EMP.

Explanation:True. Default behavior without a control file is APPEND, adding new rows (3, Curl, 4 and 4, Bob, 4) to EMP. Existing rows (1, Alan, 2, 2, Ben, 2) remain unless constrained (e.g., unique key violations).

Mechanics:SQL*Loader processes each line of emp.dat, skipping duplicates if constrained, appending otherwise.

D. It generates a SQL script that it uses to load data from EMP.DAT to EMP.

Explanation:False. SQL*Loader doesn’t generate SQL scripts; it uses direct path or conventional path loading, not SQL scripts. The log contains control file syntax, not a script.

E. It overwrites all data in EMP with data from EMP.DAT.

Explanation:False. REPLACE or TRUNCATE would overwrite, but these require a control file with those options. Default APPEND preserves existing data.