EDM 1-2 Reviewer for Diagnostic Exam

Database

Organized collection of data.

Table

Stores data in rows and columns.

Row

One record in a table.

Column

One data field or attribute.

Primary Key

Uniquely identifies a row.

Foreign Key

Links one table to another.

UNIQUE

Prevents duplicate values.

Index

Speeds up data retrieval.

CHAR

Fixed-length character data type.

SELECT

Retrieves data.

INSERT

Adds new data.

UPDATE

Modifies existing data.

DELETE

Removes data.

SQL

Language for querying and modifying database data.

ACID

Properties that ensure reliable transactions.

Atomicity

Transaction is all-or-nothing.

Consistency

Keeps data valid.

Isolation

Transactions do not improperly interfere.

Durability

Committed data remains saved.

PL/SQL

Oracle's procedural programming extension to SQL.

Procedure

Stored program that performs a task.

Function

Reusable program that normally returns a value.

Cursor

Processes query results row-by-row.

Exception

Handles errors in PL/SQL.

Oracle APEX

Low-code platform for building database web applications.

Performance Tuning

Improving database speed and efficiency.

CPU

Processes database operations.

Memory

Stores actively used data and work areas.

I/O

Reading and writing data to storage.

Latency

Delay in data communication.

Bandwidth

Amount of data transferable over a network.

V$ Views

Real-time or cumulative Oracle performance views.

V$SYSSTAT

Instance-level performance statistics.

V$STATNAME

Names/descriptions of statistics.

V$SESSION

Information about database sessions.

V$SQL

Information about SQL statements.

V$LATCH

Latch performance statistics.

DB Time

Total time spent doing database work.

DB CPU

Database time spent using CPU.

Wait Event

Reason a session is waiting.

AWR

Stores historical database performance data.

AWR Snapshot

Performance data captured at a point in time.

AWR Baseline

Normal performance period used for comparison.

ASH

Detailed history of active database sessions.

ADDM

Automatically analyzes performance problems.

SQL Monitoring

Real-time monitoring of SQL execution.

SQL Tuning Advisor

Analyzes SQL and recommends improvements.

SQL Performance Analyzer

Compares SQL performance before and after changes.

Database Replay

Replays captured production workloads in a test system.

SQL Trace

Records detailed SQL execution information.

TKPROF

Converts SQL trace files into readable reports.

SGA

Shared memory used by Oracle.

Buffer Cache

Stores database blocks in memory.

Shared Pool

Stores SQL, PL/SQL, and metadata.

Result Cache

Stores reusable query results.

PGA

Private memory used by individual Oracle processes.

Bind Variable

Placeholder that helps reuse SQL execution plans.

Hard Parse

Full parsing and optimization of a SQL statement.

Latch

Protects shared memory structures.

B-Tree Index

Common general-purpose Oracle index.

Index Rebuild

Recreates an index.

Index Coalesce

Reorganizes index blocks with less disruption.

Fragmentation

Inefficiently scattered or unused storage space.

Row Migration

Row moves because it no longer fits in its original block.

Row Chaining

Row is split across multiple blocks.

SHRINK SPACE

Reclaims unused table or index space.

High Water Mark

Highest block considered used in a table.

Compression

Reduces storage space used by data.

DBMS_COMPRESSION

Oracle package for compression information.

In-Memory Column Store

Stores columnar data in memory for faster analytics.

INMEMORY_SIZE

Controls In-Memory area size.

NO INMEMORY

Prevents an object from being stored in In-Memory.

Redo Log

Records database changes for recovery.

LGWR

Writes redo records to redo logs.

DBWR

Writes modified database blocks to disk.

ARCn

Archives filled redo log files.

CKPT

Updates checkpoint information.

EM Express

Web-based Oracle database monitoring tool.

Performance Hub

Displays database performance information.

Top Sessions

Shows sessions causing the most load.

Load Profile

Shows overall workload activity.

Enterprise Manager Cloud Control

Comprehensive Oracle database management platform.

AWR

Historical performance.

ASH

Active session history.

ADDM

Diagnoses performance issues.

SQL Monitoring

Watches SQL in real time.

SQL Tuning Advisor

Recommends SQL improvements.

SQL Performance Analyzer

Compares SQL before and after changes.

Database Replay

Replays complete workloads.