Oracle does NOT support a CASCADE UPDATE constraint.
Answer: A
Correct answer: True
Oracle supports ON DELETE CASCADE but has no ON UPDATE CASCADE, so a change to a parent key value cannot be propagated to the children automatically. The remedy is either a trigger or, more usually, a surrogate primary key whose value never needs to change - which removes the problem rather than working around it.
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Sequences guarantee valid surrogate key values.
Answer: B
Correct answer: False
A sequence guarantees only uniqueness of the numbers it issues. Values are lost when a transaction rolls back or an instance fails, so gaps appear; nothing forces the value to be used in the intended column; and a value can be inserted directly, bypassing the sequence and colliding with it later. Uniqueness is not the same as validity.
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Oracle will let you define Notepad as your default editor, and whenever you type NOTEPAD, SQL*Plus will invoke Notepad.
Answer: B
Correct answer: False
The first half is right and the second wrong. An editor is defined once, with DEFINE _EDITOR, and is then invoked by typing EDIT - not by typing the editor’s own name, which SQL*Plus would not recognise as a command. The point of the arrangement is that scripts using EDIT work whatever editor has been chosen.
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Oracle commands, column names, table names, view names and all other database elements are case sensitive.
Answer: B
Correct answer: False
They are case insensitive. Commands, table names, column names and view names may be written in any case and are matched the same way, which is why SELECT * FROM Customer and select * from CUSTOMER are identical. Case matters only within quoted strings, and in identifiers deliberately created inside double quotes.
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If there is only one statement and no ambiguity about what is wanted, Oracle will treat the semicolon and slash as the same.
Answer: A
Correct answer: True
With a single unambiguous statement in the buffer, ending it with a semicolon and typing a slash on the next line have the same effect: the statement is executed. The two are not interchangeable in general, however - a PL/SQL block contains semicolons within its own body, so only a slash can submit it.
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In SQL*Plus, the DESCRIBE command displays the structure of a table.
Answer: A
Correct answer: True
DESCRIBE, commonly abbreviated to DESC, lists a table’s columns with their data types and whether each accepts nulls. It reports the definition only and returns none of the stored rows.
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The only time that case matters is inside quotation marks of strings.
Answer: A
Correct answer: True
Case is significant only where the characters are data rather than names: inside a quoted string literal, so that WHERE name = 'Smith' does not match SMITH. Everything else - keywords, table names, column names - is matched without regard to case. Identifiers created inside double quotes are the one further exception.
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You can use the DROP statement to remove structures from the database.
Answer: A
Correct answer: True
DROP removes a structure from the database entirely - DROP TABLE, DROP VIEW, DROP INDEX, DROP SEQUENCE. It is distinct from DELETE, which removes rows and leaves the table in place, and from ALTER, which changes a structure without removing it.
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Oracle, the world's most popular DBMS, is powerful and robust, running on many different operating systems.
Answer: A
Correct answer: True
Oracle runs on Unix, Linux, Windows and mainframe platforms alike, and it has long led the market for enterprise relational database systems. The claim is a general one about the product’s reach rather than a technical point, and the portability is the part that matters to a developer: the same SQL and PL/SQL run on any of those platforms.
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