Vendor Name: PostgreSQL
Exam code: PGCES-02
Exam Name: PostgreSQL CE 8 Silver
Click the link below to get full version
http://www.certifyguide.com/exam/PGCES-02/
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Question: 1
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Select two suitable statements
regarding the following SQL statement:
CREATE TRIGGER trigger_1 AFTER
UPDATE ON sales FOR EACH ROW EXECUTE PROCEDURE write_log();
A. It is defining a trigger
"trigger_1".
B. Every time 'UPDATE' is
executed on the "sales" table, the "write_log" function is
called once.
C. The "write_log"
function is called before 'UPDATE' takes place.
D. 'UPDATE' is not executed if
"write_log" returns NULL.
E. 'DROP TRIGGER trigger_1 ON
sales;' deletes the defined trigger.
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Answer: A, E
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Question: 2
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Select two transaction
isolation levels supported in PostgreSQL.
A. DIRTY READ
B. READ COMMITTED
C. REPEATABLE READ
D. PHANTOM READ
E. SERIALIZABLE
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Answer: B, E
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Question: 3
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PostgreSQL can use an index to
access a table. Select two incorrect statements about indexes.
A. An index is created by
'CREATE INDEX', and deleted by 'DROP INDEX'.
B. By using an index
effectively, searching and sorting performs faster.
C. There are B-tree, Hash,
R-tree and GiST index types.
D. By creating an index,
performance always improves.
E. Creating an unused index
does not affect the performance of a database at all.
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Answer: D, E
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Question: 4
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Select two incorrect
statements regarding 'DOMAIN'.
A. When defining a domain, you
can add a default value and constraints to the original data.
B. Domain is a namespace
existing between databases and objects such as tables.
C. A domain is created by
'CREATE DOMAIN'.
D. A domain can be used as a
column type when defining a table.
E. To define a domain, both
input and output functions are required.
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Answer: B, E
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Question: 5
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Select two suitable statements
regarding the data types of PostgreSQL.
A. One field can handle up to
1GB of data.
B. 'n' in CHARACTER(n)
represents the number of bytes.
C. Only the INTEGER type can
be declared as an array.
D. There is a non-standard
PostgreSQL data type, called Geometric data type, which handles 2dimensional
data.
E. A large object data type
can be used to store data of unlimited size.
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Answer: A, D
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Question: 6
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The table "score" is
defined as follows:
gid | score
-----+-------
1 | 70 1 |
60 2 | 100
3 | 80 3 |
50
The following query was executed.
Select the number of rows in the result.
SELECT gid, max(score) FROM
score GROUP BY gid HAVING max(score) > 60;
A. 1 row
B. 2 rows
C. 3 rows
D. 4 rows
E. 5 rows
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Answer: C
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Question: 7
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Table "t1" is
defined as follows: CREATE TABLE t1 (value VARCHAR(5)); A set of SQL statements
were executed in the following order. Select the number of rows that table
"t1" has after execution. BEGIN; INSERT INTO t1 VALUES ('AA');
SAVEPOINT point1; INSERT INTO t1 VALUES ('BB'); SAVEPOINT point2; INSERT INTO
t1 VALUES ('CC'); ROLLBACK TO point1; INSERT INTO t1 VALUES ('DD'); END;
A. 1 row
B. 2 rows
C. 3 rows
D. 4 rows
E. 0 rows
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Answer: B
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Question: 8
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Select two suitable statements
about sequences.
A. A sequence always returns a
4-byte INTEGER type value, so the maximum value is 2147483647.
B. A sequence is defined by
'CREATE SEQUENCE', and deleted by 'DROP SEQUENCE'.
C. Although the
"nextval" function is called during a transaction, it will have no
effect if that transaction is rolled back.
D. A sequence always generates
0 or consecutive positive numbers.
E. A sequence number can be
set by calling the "setval" function.
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Answer: B, E
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Question: 9
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The "sample" table
consists of the following data: How many rows are returned by executing the
following SQL statement? SELECT DISTINCT ON (data) * FROM sample;
A. 2 rows
B. 3 rows
C. 4 rows D. 5 rows
E. 6 rows
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Answer: B
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Question: 10
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The following SQL statements
were executed using psql.
Select the appropriate
statement about the result.
LISTEN sign_v; BEGIN; NOTIFY
sign_v; COMMIT;
LISTEN sign_v;
A. At the point that 'NOTIFY
sign_v' is executed, a message that starts with
"Asynchronous
notification 'sign_v' received" is output.
B. At the point that 'COMMIT'
is executed, a message that starts with "Asynchronous notification
'sign_v' received" is output.
C. At the point that 'SELECT *
FROM pg_user;" is executed, a message that starts with "Asynchronous
notification 'sign_v' received" is output.
D. When 'LISTEN sign_v' is
executed for the second time, a message that starts with "Asynchronous
notification 'sign_v' received" is output.
E. The message
"Asynchronous notification 'sign_v' received" is not received while
in this connection.
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Answer: B
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Question: 11
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Select the correct SQL
statement which concatenates strings 'ABC' and 'abc' to form 'ABCabc'.
A. SELECT 'ABC' . 'abc';
B. SELECT cat('ABC', 'abc')
FROM pg_operator;
C. SELECT 'ABC' + 'abc';
D. SELECT 'ABC' + 'abc' FROM
pg_operator;
E. SELECT 'ABC' || 'abc';
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Answer: E
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Question: 12
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Select two correct
descriptions about views.
A. A view is created by
'DECLARE VIEW', and deleted by 'DROP VIEW'.
B. A view is a virtual table
which does not exist.
C. A view is created to
simplify complicated queries.
D. You can create a view with
the same name as already existing tables.
E. A view only exists while
the postmaster is running, and is deleted when the postmaster stops.
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Answer: B, C
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Question: 13
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Table "t1" is
defined below. Table "t1" has a column "id" of type
INTEGER, and a column "name" of type TEXT. t1: The following SQL is
executed while client "A" is connected. BEGIN;
SELECT * FROM t1 WHERE id = 2
FOR UPDATE; SELECT * FROM t1 WHERE id = 1 FOR UPDATE; -- (*) While the second
'SELECT' statement, shown with (*), is being executed, a separate client
"B" connects and executes the following SQL. Select the correct
statement about the execution results. UPDATE t1 SET name = 'turtle' WHERE id =
2; Note: the default transaction isolation level is set to "read committed".
A. The update process for
client "B" is blocked until the current connection for client
"A" is finished.
B. The update process for
client "B" is blocked until the current transaction for client
"A" is finished.
C. The 'UPDATE' process for
client "B" proceeds regardless of the condition of client
"A".
D. The process of client
"B" immediately generates an error.
E. The processes for both
clients are blocked, and an error stating that a deadlock has been detected is
generated.
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Answer: B
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Question: 14
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SQL statements were executed
in the following order:
CREATE TABLE fmaster
(id INTEGER PRIMARY KEY, name
TEXT);
CREATE TABLE ftrans
(id INTEGER REFERENCES fmaster
(id), stat INTEGER, date DATE);
INSERT INTO fmaster VALUES (1,
'itemA');
INSERT INTO ftrans VALUES (1,
1, CURRENT_DATE);
Select two SQL statements that
will generate an error when executed next.
A. INSERT INTO ftrans VALUES
(1, 1, CURRENT_DATE);
B. INSERT INTO ftrans VALUES
(2, 1, '2007-07-07');
C. UPDATE fmaster SET name =
'itemAX' WHERE id = 1;
D. UPDATE fmaster SET id = 100
WHERE id = 1;
E. UPDATE ftrans SET id = 200
WHERE id = 1;
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Answer: A, C
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Question: 15
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Select three SQL statements
which return NULL.
A. SELECT 0 = NULL;
B. SELECT NULL != NULL;
C. SELECT NULL IS NULL;
D. SELECT NULL;
E. SELECT 'null'::TEXT;
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Answer: A, B, D
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