Oracle Database Study Flashcards
Enterprise object-relational database standard deployed across mission-critical corporate environments. Click any card to flip and test your knowledge.
What is SGA in Oracle Architecture?
System Global Area (SGA) is the shared memory region containing data buffer cache, shared pool, and redo log buffer.
What is PGA in Oracle Database?
Program Global Area (PGA) is private memory allocated for each server process executing SQL operations.
How does ROWNUM differ from FETCH FIRST in Oracle?
ROWNUM assigns row numbers during fetch, whereas FETCH FIRST N ROWS ONLY is standard ANSI pagination syntax.
What is NVL() in Oracle SQL?
NVL(expr1, expr2) replaces NULL with expr2 if expr1 evaluates to NULL.
What is PL/SQL?
Procedural Language/SQL (PL/SQL) is Oracle's extension providing procedural constructs like loops, variables, and exceptions.
What is a Materialized View in Oracle?
A database object storing pre-computed query results that can be refreshed on demand or commit.
What is Oracle Flashback Query?
Enables querying table data state as it existed at a past timestamp or SCN number.
What is a Table Space in Oracle?
Logical storage unit grouping physical data files (.dbf) containing tables and indexes.
What is CONNECT BY used for?
Hierarchical query clause used to traverse parent-child tree relationships in Oracle SQL.
What is a Sequence in Oracle?
Database object that generates sequential unique integers (using NEXTVAL and CURRVAL).
Need practical SQL queries for Oracle Database?
Explore our ready-to-use copy-paste query recipes in the Cookbook.