Question

Design Of Database System Course

True or False

1. In MySQL, it is possible to create a table by using the definition of another table.

2. {(t.lname) | s ∈ Student, s.stuId = t.stuId, t ∉ Graduate_Student, s.major = ‘CS’} is a safe relational calculus expression.

3. In SQL, it is possible to insert multiple rows into a table using a single INSERT statement.

Answer 1

1. In MySQL, it is possible to create a table by using the definition of another table.

ANSWER :- "TRUE"

Example:

CREATE TABLE new_table LIKE old_table; 

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2. {(t.lname) | s ∈ Student, s.stuId = t.stuId, t ∉ Graduate_Student, s.major = ‘CS’} is a safe relational calculus expression.

ANSWER :- "TRUE"

EXPLANATION :

"A SAFE EXPRESSION is one that is guaranteed to yield a finite number of tuples as its results. Otherwise, it is called UNSAFE."
Example:

{ t | not(EMPLOYEE) }
is UNSAFE!

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3.  In SQL, it is possible to insert multiple rows into a table using a single INSERT statement.

ANSWER :- "TRUE"

Example :

INSERT INTO table_name (column_list)
VALUES
    (value_list_1),
    (value_list_2),
    ...
    (value_list_n);