PostgreSQL - VACUUM ANALYZE EXPLAIN NOTIFY

Select the correct statement that records the space occupied by deleted or updated rows for later reuse, and also updates statistics.

A. VACUUM
B. VACUUM ANALYZE
C. EXPLAIN
D. EXPLAIN ANALYZE
E. NOTIFY
F. None of the above

Answer: [B]
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PostgreSQL - ANALYZE quiz

What does the following command do?
Choose the correct answer below.
Note: "psql=#" is the command prompt for psql.
psql=# ANALYZE xyz;

A. Collects statistical information related to the content of the database xyz.
B. Collects statistical information related to the content of the table xyz.
C. Outputs statistical information related to the content of the table xyz.
D. No ANALYZE command in PostgreSQL, error will occur.
E. None of the above
F. Both B & C

Answer: [B]
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PostgreSQL quiz: stored procedure execution

Assume that you have a table contact and a stored procedure called insert_contact as the following screenshots

Which one below is correct?

A. CALL insert_contact(‘John’,'Tran’);

B. EXECUTE insert_contact(‘John’,’Tran’);

C. SELECT insert_contact(‘John’,’Tran’)

D. Both A & B

E. Error in the store procedure code

F. None of the above

 

Answer: [C]

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PostgreSQL license

Select the most suitable statement about the PostgreSQL license from below.

A. PostgreSQL is distributed under the GPL license.
B. PostgreSQL is distributed under the PostgreSQL license.
C. PostgreSQL is distributed under the LGPL license.
D. PostgreSQL is distributed under the BSD license.
E. PostgreSQL is distributed under the X11(MIT) license.

 

Answer: [D]

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PostgreSQL Contactenation

Which query is correct in PostgreSQL?

A. SELECT 'Test' . 'query';
B. SELECT cat('Test','query') FROM dual;
C. SELECT 'Test' + 'query';
D. SELECT 'Test' + 'query' FROM dual;
E. SELECT 'Test' || 'query';

Answer:[E]
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Port number

What are the default port numbers of SQL Server and MySQL in sequence?

A. 3306 and 5432
B. 1433 and 3306
C. 1433 and 5432
D. 3306 and 1433
E. 5432 and 1433
F. 5432 and 3306

Answer:[B]
Explanation: SQL Server:1433, MySQL:3306, PostgreSQL: 5432
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