To learn more about the rules of using the GROUP BY clause and aggregate functions, read Chapter 3.. To learn more about table and column names, read Chapter 6.. When altering an existin
Trang 1SQL Fundamentals I Assessment Test xlv
36 A view is created using the following code Which of the following operations are permitted
on the view?
CREATE VIEW USA_STATES
AS SELECT * FROM STATEWHERE CNT_CODE = 1WITH READ ONLY;
A SELECT
B SELECT, UPDATE
C SELECT, DELETE
D SELECT, INSERT
37 You query the database with the following:
SELECT PRODUCT_ID FROM PRODUCTSWHERE PRODUCT_ID LIKE ‘%S\_J\_C’ ESCAPE ‘\’;
Choose the two PRODUCT_ID strings that will satisfy the query
SALARY NUMBER (14,2)Which query is most appropriate to use if you need to find the employees who were hired before January 1, 1998 and have a salary greater than 5,000 or less than 1,000?
A SELECT emp_name FROM employee
WHERE hire_date > TO_DATE(‘01011998’,’MMDDYYYY’) AND SALARY < 1000 OR > 5000;
B SELECT emp_name FROM employee
WHERE hire_date < TO_DATE(‘01011998’,’MMDDYYYY’) AND SALARY < 1000 OR SALARY > 5000;
C SELECT emp_name FROM employee
WHERE hire_date < TO_DATE(‘01011998’,’MMDDYYYY’) AND (SALARY < 1000 OR SALARY > 5000);
D SELECT emp_name FROM employee
WHERE hire_date < TO_DATE(‘01011998’,’MMDDYYYY’) AND SALARY BETWEEN 1000 AND 5000;
Trang 2xlvi SQL Fundamentals I Assessment Test
39 What happens when you issue the following command? (Choose all that apply.)
TRUNCATE TABLE SCOTT.EMPLOYEE;
A All the rows in the table EMPLOYEE owned by SCOTT are removed.
B The storage space used by the table EMPLOYEE is released (except the initial extent).
C If foreign key constraints are defined to this table using the ON DELETE CASCADE
clause, the rows from the child tables are also removed
D The indexes on the table are dropped.
E You cannot truncate a table if triggers are defined on the table.
40 Which two statements will drop the primary key defined on table EMP? The primary key
name is PK_EMP
A ALTER TABLE EMP DROP PRIMARY KEY;
B DROP CONSTRAINT PK_EMP;
C ALTER TABLE EMP DROP CONSTRAINT PK_EMP;
D ALTER CONSTRAINT PK_EMP DROP CASCADE;
E DROP CONSTRAINT PK_EMP ON EMP;
Trang 3Answers to SQL Fundamentals I Assessment Test
1 B In the arithmetic operators, unary operators are evaluated first, then multiplication
and division, and finally addition and subtraction The expression is evaluated from left to right For more information about order of evaluation, see Chapter 1
2 A, C The CREATE FORCE VIEW statement can be used to create a view before its base table
is created In versions prior to Oracle 11g, any modification to the table will invalidate the view In Oracle 11g, the view will be invalidated only if the columns used in the view
are modified in the base table Use the ALTER VIEW <view name> COMPILE statement to recompile the view See Chapter 7 to learn more about views
3 C CONCAT will return a non-NULL if only one parameter is NULL Both CONCAT parameters
would need to be NULL for CONCAT to return NULL The NULLIF function returns NULL if the two parameters are equal The LENGTH of a NULL is NULL INSTR will return NULL if NULL is passed in and the tangent of a NULL is NULL For more information about NULL values, see Chapter 2
4 C Group functions cannot appear in the WHERE clause To learn more about group
func-tions, see Chapter 3
5 B When updating multiple columns in a single UPDATE statement, the column assignments
in the SET clause must be separated by commas, not AND operators To read more about DML statements (INSERT, UPDATE, and DELETE), refer to Chapter 5
6 C Since job_id is used in the SELECT clause, it must be used in the GROUP BY clause also
To learn more about the rules of using the GROUP BY clause and aggregate functions, read Chapter 3
7 B The BFILE datatype stores only the locator to an external file in the database; the actual
data is stored as an operating system file BLOB, NCLOB, and CLOB are the other large
object data types in Oracle 11g UROWID is Universal ROWID datatype and EXTERNAL
is a not a valid datatype See Chapter 6 for information about datatypes
8 C The statement will work without error Option B would be correct if you used the WITH
CHECK OPTION clause in the subquery See Chapter 4 for more information about subqueries
9 A, E An outer join on both tables can be achieved using the FULL OUTER JOIN syntax
You can specify the join condition using the ON clause to specify the columns explicitly or using the USING clause to specify the columns with common column names Options B and
D would result in errors In option B, the join type is not specified; OUTER is an optional keyword In option D, CROSS JOIN is used to get a Cartesian result, and Oracle does not expect a join condition To learn more about joins, read Chapter 4
Trang 4xlviii Answers to SQL Fundamentals I Assessment Test
10 A, B The index contains all the information needed to satisfy the query in option A, and a
full-index scan would be faster than a full-table scan A subset of index columns is specified
in the WHERE clause of option B; hence, Oracle 11g can use the index For more information
on indexes, see Chapter 7
11 D The CREATE SEQUENCE statement will create an increasing sequence that will start with
1, will increment by 1, and will be unaffected by the rollback A rollback will never stuff vales back into a sequence See Chapter 7 to learn more about sequences
12 B, C Primary and unique key constraints can be enforced using nonunique indexes
Unique constraints allow NULL values in the columns, but primary keys do not Read ter 6 to learn more about constraints
Chap-13 B The SYSDATE function returns the date and time on the server where the database
instance is started CURRENT_DATE returns the local date and time For information on the built-in date functions, read Chapter 2
14 D The first INSERT statement and last INSERT statement will be saved in the database The
ROLLBACK TO A statement will undo the second and third inserts To know more about transaction control and ROLLBACK, read Chapter 5
15 B There should be at least n-1 join conditions when joining n tables to avoid a Cartesian
join To learn more about joins, see Chapter 4
16 C The table and column names can include only three special characters: #, $, and _ No
other characters are allowed in the table name You can have letters and numbers in the table name To learn more about table and column names, read Chapter 6
17 B, D You can use the IS NULL or IS NOT NULL operator to search for NULLs or non-NULLs
in a column Since NULLs are sorted higher, they appear at the bottom of the result set in an ascending-order sort See Chapter 1 for more information about sorting NULL values
18 D COUNT (<column_name>) does not include the NULL values, whereas COUNT (*) includes
the NULL values No other aggregate function takes NULL into consideration To learn more about aggregate functions, read Chapter 3
19 E These statements don’t account for possible NULL values in the BONUS column For more
information about NULL values, see Chapter 2
20 D Using the ALTER TABLE statement, you can add new columns, rename existing columns,
and drop existing columns To learn more about managing tables, read Chapter 6
21 B Since DEPARTMENT_ID is NULL for employee 178, NULL will be sorted after the non-NULL
values when doing an ascending-order sort Since I did not specify the sort order or the NULLS FIRST clause, the defaults are ASC and NULLS LAST Read Chapter 1 for more infor-mation on SELECT and sort orders
22 D, E, F, G The INTERVAL DAY TO SECOND datatype is used to store an interval
between two datetime components See Chapter 6 for more information on the INTERVAL and TIMESTAMP datatypes
Trang 5Answers to SQL Fundamentals I Assessment Test xlix
23 D, E In the join view, CITY is the key-preserved table You can update the columns of
the CITY table, except STATE_CD, because STATE_CD is not part of the view definition (the STATE_CD column in the view is from the STATE table) Since I did not include the STATE_CD column from the CITY table, no INSERT operations are permitted (STATE_CD is part of the primary key) If the view were defined as follows, all the columns of the CITY table would have been updatable, and new records could be inserted into the CITY table
CREATE OR REPLACE VIEW state_city AS SELECT b.state_cd, a.state_name, b.city_cd, b.city_name FROM states a, cities b
WHERE a.state_cd = b.state_cd;
See Chapter 7 for more information about views
24 B When altering an existing column to add a NOT NULL constraint, no rows in the table
should have NULL values In the example, there are two rows with NULL values Creating and modifying tables are discussed in Chapter 6
25 D NATURAL JOIN and JOIN…USING clauses will not allow alias names to be used Since a
self-join is getting data from the same table, you must include alias names and qualify umn names To learn more about ANSI join syntax, read Chapter 4
col-26 E The TRUNC function used with a negative second argument will truncate to the left of the
decimal To learn more about TRUNC and other numeric functions, read Chapter 2
27 C Oracle creates unique indexes for each unique key and primary key defined in the table
The table ADDRESSES has one unique key and a primary key Indexes will not be created for NOT NULL or foreign key constraints Constraints are discussed in Chapter 6
28 D Although there is no error in this statement, the statement will not return the desired
result When a NULL is compared, you cannot use the = or != operator; you must use the IS NULL or IS NOT NULL operator See Chapter 1 for more information about the comparison operators
29 A You cannot explicitly change the next value of a sequence You can set the MAXVALUE or
INCREMENT BY value to a negative number, and NOCYCLE tells Oracle to not reuse a sequence number See Chapter 7 for more information
30 B Private synonyms override public synonyms, and tables or views owned by the user
always resolve first To learn more about synonyms, see Chapter 7
31 C, D When COMMIT is executed, all locks are released, all savepoints are erased, and
que-ries started before the COMMIT will constitute a read-consistent view using the undo mation To learn more about COMMIT, read Chapter 5
infor-32 B, C The operators OR and AND are used to add more joining conditions to the query NOT is
a negation operator, and a comma is used to separate column names and table names Read more about joins and join conditions in Chapter 4
Trang 6l Answers to SQL Fundamentals I Assessment Test
33 C Since you are finding the aggregate of the aggregate, you should not use nonaggregate
columns in the SELECT clause To read more about nesting of aggregate functions, see Chapter 3
34 B You can create primary key, foreign key, and unique key constraints on a view The
con-straints on views are not enforced by Oracle To enforce a constraint, it must be defined on
a table Views can be created with the WITH CHECK OPTION and READ ONLY attributes ing view creation Read Chapter 7 to learn more
dur-35 A, C The maximum lengths of CHAR and VARCHAR2 columns can be defined in
charac-ters or bytes BYTE is the default To learn more about CHAR and VARCHAR2 datatypes, read Chapter 6
36 A When the view is created with the READ ONLY option, only reads are allowed from the
view See Chapter 7 to learn more about creating views as read-only
37 A, D The substitution character % can be substituted for zero or many characters The
substitution character _ does not have any effect in this query because an escape character precedes it, so it is treated as a literal Read Chapter 1 to learn more about substitution characters
38 C You have two main conditions in the question: one on the hire date and the other on
the salary So, you should use an AND operator In the second part, you have two options:
the salary can be either more than 5,000 or less than 1,000, so the second part should be enclosed in parentheses and should use an OR operator Option B is similar to option C except for the parentheses, but the difference changes the meaning completely Option B
would select the employees who were hired before January 1, 1998 or have a salary greater
than 5,000 or less than 1,000 Read Chapter 1 to learn more about writing queries using filtering conditions
39 A, B The TRUNCATE command is used to remove all the rows from a table or cluster By
default, this command releases all the storage space used by the table and resets the table’s high-water mark to zero No indexes, constraints, or triggers on the table are dropped or disabled If there are valid foreign key constraints defined to this table, you must disable all of them before truncating the table Chapter 5 includes a comparison between using TRUNCATE and the DELETE statement to remove rows
40 A, C Since there can be only one primary key per table, the syntax in option A works Any
constraint (except NOT NULL) can be dropped using the syntax in option C Learn more about constraints in Chapter 6
Trang 7Administration I Assessment Test
1 Which of the following is not considered part of Oracle Database?
A Data files
B Redo logs
C Pfile and spfile
D Control files
2 The following are the steps required for relocating a data file belonging to the USERS
tablespace Order the steps in their proper sequence
A Copy the file /disk1/users01.dbf to /disk2/users01.dbf using an OS command.
B ALTER DATABASE RENAME FILE ‘/disk1/users01.dbf’ TO ‘/disk2/users01.dbf’
C ALTER TABLESPACE USERS OFFLINE
D ALTER TABLESPACE USERS ONLINE
3 You manage one non-Oracle Database and several Oracle Databases An application needs
to access the non-Oracle database as if it were part of the Oracle database What tool allows you to do this? (Choose the best answer.)
A Oracle Advanced Security
B Oracle Connection Manager
C Heterogeneous Services
D Oracle Net
E None of the above
4 Choose two utilities that can be used to apply CPU patches on an Oracle 11g database.
A Oracle Universal Installer
Trang 8lii Administration I Assessment Test
6 Which of the following statements is not always true? (Choose two.)
A Every database should have at least two tablespaces.
B Every database should have at least two data files.
C Every database should have at least three multiplexed redo logs.
D Every database should have at least three control files.
7 Which statement about the initialization-parameter files is true?
A The pfile and spfile can be modified using the ALTER SYSTEM statement.
B You cannot have both an spfile and a pfile under the $ORACLE_HOME/dbs directory.
C The pfile is used only to read by the Oracle instance, whereas the spfile is used to read
and write to
D On Windows systems, pfile and spfiles are not used because parameters are modified
using the system registry
8 Which initialization parameter determines the location of the alert log file?
A DIAGNOSTIC_DEST
B BACKGROUND_DUMP_DEST
C ALERT_LOG_DEST
D USER_DUMP_DEST
9 Which parameter is used to set up the directory for Oracle to create data files if the
DATAFILE clause does not specify a filename when creating or altering tablespaces?
Trang 9Administration I Assessment Test liii
11 A constraint is created with the DEFERRABLE INITIALLY IMMEDIATE clause What does
this mean?
A Constraint checking is done only at commit time.
B Constraint checking is done after each SQL, but you can change this behavior by
speci-fying SET CONSTRAINTS ALL DEFERRED
C Existing rows in the table are immediately checked for constraint violation.
D The constraint is immediately checked in a DML operation, but subsequent constraint
verification is done at commit time
12 You have just made changes to the listener.ora file for the listener called listener1
using Oracle Net Manager Which of the following commands or combinations of commands would you use to put the changes into effect with the least amount of client disruption?
A lsnrctl stop listener1 followed by lsnrctl start listener1
14 If you are updating one row in a table using the ROWID in the WHERE clause (assume that the
row is not already in the buffer cache), what will be the minimum amount of information copied to the database buffer cache?
A The entire table is copied to the database buffer cache.
B The extent is copied to the database buffer cache.
C The block is copied to the database buffer cache.
D The row is copied to the database buffer cache.
15 When you are configuring Shared Server, which initialization parameter would you likely
Trang 10liv Administration I Assessment Test
16 To grant the SELECT privilege on the table HR.CUSTOMERS to all users in the database, which
statement would you use?
A GRANT SELECT ON HR.CUSTOMERS TO ALL USERS;
B GRANT SELECT ON HR.CUSTOMERS TO ALL;
C GRANT SELECT ON HR.CUSTOMERS TO ANONYMOUS;
D GRANT SELECT ON HR.CUSTOMERS TO PUBLIC;
17 Which of the following commands is most likely to generate an error message? (Choose two.)
A ALTER SYSTEM SET UNDO_MANAGEMENT=AUTO SCOPE=MEMORY;
B ALTER SYSTEM SET UNDO_MANAGEMENT=AUTO SCOPE=SPFILE;
C ALTER SYSTEM SET UNDO_MANAGEMENT=MANUAL SCOPE=MEMORY;
D ALTER SYSTEM SET UNDO_MANAGEMENT=MANUAL SCOPE=SPFILE;
E ALTER SYSTEM SET UNDO_TABLESPACE=RBS1 SCOPE=BOTH;
18 The Automatic Workload Repository (AWR) is primarily populated with performance
sta-tistics by which Oracle 11g background process?
A Startup will fail because you have not completed the instance recovery.
B Oracle automatically performs recovery; all committed changes are written to data
files
C During instance recovery you have the option to selectively commit uncommitted
transactions
D After the database starts, you have to manually clean out uncommitted transactions
from the transaction table
20 Which storage parameter is used to make sure that each extent is a multiple of the value
specified on dictionary-managed tablespaces?
A MINEXTENTS
B INITIAL
C MINIMUM EXTENT
D MAXEXTENTS
Trang 11Administration I Assessment Test lv
21 Which of the following is the utility that you can use to test the network connections
E None of the above
22 What is the difference between a unique key constraint and a primary key constraint?
A A unique key constraint requires a unique index to enforce the constraint, whereas a
primary key constraint can enforce uniqueness using a unique or nonunique index
B A primary key column can be NULL, but a unique key column cannot be NULL.
C A primary key constraint can use an existing index, but a unique constraint always
creates an index
D A unique constraint column can be NULL, but the primary key column(s) cannot
be NULL
23 Which of the following conditions prevents you from being able to insert into a view?
A A TO_NUMBER function on one of the base table columns
B A CONNECT BY clause in the view definition
C A column of type RAW
D All of the above
24 Which parameter is used to enable the Automatic Memory Management feature of the
25 Undo data in an undo tablespace is not used for which of the following purposes?
A Providing users with read-consistent queries
B Rolling forward after an instance failure
C Flashback queries
D Recovering from a failed transaction
E Restoring original data when a ROLLBACK is issued
Trang 12lvi Administration I Assessment Test
26 Which initialization parameter determines the window of flashback database operation?
A DB_RECOVERY_FILE_DEST_SIZE
B DB_FLASHBACK_RETENTION_TARGET
C FAST_START_MTTR_TARGET
D No initialization parameter; the window is determined by the RMAN backups.
27 When you started the Oracle 11g database, you got an “ORA-01157: cannot identify data
file…” error After invoking RMAN, which command would you use before performing REPAIR FAILURE?
D The user who creates the directory
29 Which of the following types of statements can use a temporary tablespace?
A An index creation
B SQL statements with a GROUP BY clause
C A hash join operation
D All of the above
30 Which of the following is false about shared servers?
A Shared servers can process requests from many users.
B Shared servers receive their requests directly from dispatchers.
C Shared servers place completed requests on a dispatcher response queue.
D The SHARED_SERVERS parameter configures the number of shared servers to start at
instance startup
31 What is accomplished when you issue the following statement?
ALTER USER JOHN DEFAULT ROLE ALL;
A John is assigned all roles created in the database.
B Existing roles remain the same, but future roles created will be enabled.
C All of John’s roles are enabled except the roles with passwords.
D All of John’s roles are enabled, including the roles with passwords.
Trang 13Administration I Assessment Test lvii
32 Which initialization parameter determines the location of the alert log file?
34 How can you prevent someone from using an all-numeric password?
A Set the initialization parameter PASSWORD_COMPLEXITY to ALPHANUM.
B Alter that user’s profile setting PASSWORD_COMPLEXITY to ALPHNANUM.
C Alter the user’s profile to use a password-verify function that performs comparisons to
validate the password
D There is no mechanism that lets you prevent an all-numeric password.
35 Which of the following advisors is used to determine whether the database read-consistency
mechanisms are properly configured?
A Undo Management Advisor
B Redo log files
C Alert log file
D Parameter file
37 In the Disk Settings section of EM Database Control’s Configure Backup Settings page,
which of the following backup settings is not configurable?
A Disk Backup Type
B Control File Autobackup Format
C Disk Backup Location
D Parallelism
Trang 14lviii Administration I Assessment Test
38 You need to copy the GL schema from production to qa_test, changing the tablespace
for indexes from gl_index to fin_indx What is the best way to satisfy these requirements?
A First, use Data Pump to copy the schema without indexes Then, change the default
tablespace for user GL in qa_test to fin_indx Next, use Data Pump to copy the indexes Finally, change the default tablespace for user GL back to gl_data
B Use the dbms_metadata package to extract table and index DDL Then, use Notepad
(or sed) to edit this DDL, changing the tablespace for the indexes Finally, run the DDL in the qa_test database
C Use Data Pump import, specifying a remap_datafile parameter to change the data
file location for indexes
D Use Data Pump import, specifying a remap_tablespace parameter to change the
tablespace location for indexes
39 Identify the statement that is not true about checkpoints.
A Instance recovery is complete when the data from the last checkpoint up to the latest
SCN in the control file has been written to the data files
B A checkpoint keeps track of what has already been written to the data files.
C The redo log group writes must occur before a Commit complete is returned to
the user
D The distance between the checkpoint position in the redo log file and the end of the redo
log group can never be more than 90 percent of the size of the largest redo log group
E How much the checkpoint lags behind the SCN is controlled by both the size of the
redo log groups and by setting the parameter FAST_START_MTTR_TARGET
40 The STATUS column of the dynamic performance view V$LOG contains what value if the
redo log file group has just been added?
A INVALID
B STALE
C UNUSED
D NULL
41 When performing Data Pump import using impdp, which of the following options is not a
valid value to the TABLE_EXISTS_ACTION parameter?
A SKIP
B APPEND
C TRUNCATE
D RECREATE
Trang 15Administration I Assessment Test lix
42 What would you do to reduce the time required to start the instance after a database crash?
A Multiplex the redo log files.
B Increase the size of the redo log files.
C Set the FAST_START_MTTR_TARGET parameter to 0.
D All of the above.
E None of the above.
Trang 16lx Answers to Administration I Assessment Test
Answers to Administration I Assessment Test
1 C Although pfiles and spfiles are physical files used to configure the Oracle instance, they
are not considered part of the database To learn more about Oracle Database structure, read Chapter 8
2 C, A, B, D To rename a data file, you need to make the tablespace offline so that Oracle
does not try to update the data file while you are renaming Using OS commands, copy the data file to the new location, and using the ALTER DATABASE RENAME FILE command
or the ALTER TABLESPACE RENAME FILE command, rename the file in the database’s trol file To rename the file in the database, the new file should exist Bring the tablespace online for normal database operation See Chapter 10 for more information
con-3 C Heterogeneous Services is the correct answer because these services provide
cross-platform connectivity to non-Oracle databases Oracle Advanced Security would not solve this application problem because it addresses security and is not accessibility to non-Oracle databases Oracle Net would be part of the solution, but another Oracle Network com-ponent is necessary Connection Manager would also not be able to accommodate this requirement on its own Read Chapter 11 to learn more
4 B, C CPU patches and interim patches can be applied using the OPatch utility or using EM
Database Control EM Database Control also includes patch search and download options
See Chapter 17 for more information
5 B, C Only the SYSTEM and UNDO tablespaces require the instance to be shut down when
their data files need recovery Read Chapter 16 to learn about database recovery
6 C, D Every database must have at least two redo log files, which may or may not be
multi-plexed Every database must have one control file It is a good idea to have more than one
con-trol file for redundancy Since SYSTEM and SYSAUX are mandatory tablespaces in Oracle 11g,
there will be at least two data files See Chapter 8 for more information
7 C A pfile is a read-only file, and no database changes are written to the pfile There is no
harm in having both an spfile and a pfile in the $ORACLE_HOME/dbs directory; Oracle will only read the spfile when starting the database On Windows systems also, you will need
a parameter-initialization file; the registry is not used Read more about parameter files in Chapter 9
8 A Oracle 11g uses the Automatic Diagnostic Repository to maintain the alert log and other
diagnostic information In pre–Oracle 11g databases, the BACKGROUND_DUMP_DEST parameter determined the alert log location; in Oracle 11g, this parameter value is ignored To learn more
about the alert log and its contents, read Chapter 9
9 B DB_CREATE_FILE_DEST specifies the directory to create data files and temp files This
directory is also used for control files and redo log files if the DB_CREATE_ONLINE_LOG_
DEST_1 parameter is not set Learn more in Chapter 10
Trang 17Answers to Administration I Assessment Test lxi
10 C The shared pool has three components: the library cache, the result cache, and the
dic-tionary cache Read Chapter 8 to learn more about SGA and Oracle instances
11 B DEFERRABLE specifies that the constraint can be deferred using the SET CONSTRAINTS
command INITIALLY IMMEDIATE specifies that the constraint’s default behavior is to date the constraint for each SQL Constraints are discussed in Chapters 7 and 10
vali-12 C Although you can use option A to stop and start the listener, doing so temporarily
dis-rupts clients attempting to connect to the database Option D is fine if you are starting and stopping the default listener called LISTENER, but you are using a nondefault listener here
Option B is not valid because RESTART is not a valid command-line argument for lsnrctl
Therefore, the best method is to use the lsnrctl reload listener1 command to load the new set of values in for the listener without disrupting connection service to the databases that the listener is servicing For more information, read Chapter 11
13 B Dynamic performance views begin with V$ The actual views have a prefix of V_$,
and the synonyms have a prefix of V$ The V$ views are based on the X$ tables, known as dynamic performance tables To learn more about dynamic performance views and tables, read Chapter 9
14 C The block is the smallest unit that can be copied to the buffer cache Information in the
dictionary cache is copied as rows To learn about buffer cache and dictionary cache, read Chapter 8
15 C Shared Server requires a shift of memory away from individual session processes to the
SGA More information has to be kept in the SGA (in the UGA) within the shared pool A large pool is configured and is responsible for most of the SGA space allocation Option C
is the correct answer The cache size and block buffers settings do not affect Shared Server
Read Chapter 11 for more information
16 D PUBLIC is the group or class of database users where all existing and future database
users belong See Chapter 12 for more information
17 A, C You cannot dynamically change the parameter UNDO_MANAGEMENT after the instance
has started You can, however, change the UNDO_TABLESPACE parameter to switch to another undo tablespace while the instance is up and running Read Chapter 13 to learn more
18 C The Manageability Monitor (MMON) process gathers performance statistics from
the system global area (SGA) and stores them in the AWR Manageability Monitor Light (MMNL) also does some AWR-related statistics gathering, but not to the extent that MMON does QMN1 is the process that monitors Oracle advanced queuing features
Memory Manager (MMAN) is the process that dynamically manages the sizes of each SGA component when directed to make changes by the Automatic Database Diagnostic Monitor (ADDM) For more information, see Chapter 14
19 B Oracle automatically performs instance recovery after a database crash or SHUTDOWN
ABORT All uncommitted changes are rolled back, and committed changes are written to data files during instance recovery Read Chapter 9 for more information
Trang 18lxii Answers to Administration I Assessment Test
20 C The MINIMUM EXTENT parameter is used to make sure each extent is a multiple of the
value specified on dictionary-managed tablespaces This parameter is useful to reduce mentation in the tablespace Oracle discourages the use of dictionary-managed tablespaces
frag-You should use locally managed tablespaces Read Chapter 10 for more information
21 D Protocols come with tools that allow you to test network connectivity One such utility
for TCP/IP is ping The user supplies either an IP address or a hostname to the ping ity It then searches the network for this address If it finds one, it displays information on data that is sent and received and how quickly it found this address The other choices are Oracle-supplied utilities Read Chapter 11 for more information
util-22 D Columns that are part of the primary key cannot accept NULL values Read Chapters 7
and 10 to learn more
23 B You cannot insert into a view that contains a CONNECT BY, ORDER BY, or GROUP BY
clause Read Chapter 13 to learn more
24 B A nonzero value for the MEMORY_TARGET parameter enables Automatic Memory
Man-agement SGA_TARGET enables Automatic Shared Memory ManMan-agement Automatic Memory Management tunes both SGA and PGA components of the memory To learn more, read Chapter 14
25 B The online redo log files are used to roll forward after an instance failure; undo data is
used to roll back any uncommitted transactions Read Chapter 13 to learn more
26 B The DB_FLASHBACK_RETENTION_TARGET parameter determines the window for the
flash-back database operation The value is specified in minutes So, a value of 1440 specifies that the flashback database window is 1 day To learn more, read Chapter 15
27 B REPAIR FAILURE works only after ADVISE FAILURE Option A, RECOVER FAILURE, is
invalid CHANGE FAILURE can be used to lower or raise the priority of a failure To learn more about automatically recovering from failures, read Chapter 16
28 C SYS is always the owner of directory object You can grant read and write privileges on
the directory to users See Chapter 17 to learn more
29 D Any operation that requires a large sort or other creation of temporary segments will
create, alter, and drop those temporary segments in the TEMPORARY tablespace See ter 12 for more information
Chap-30 B Shared servers can process requests from many users The completed requests are placed
into the dispatchers’ response queues The servers are configured with the SERVERS ter However, shared servers do not receive requests directly from dispatchers The requests are taken from the request queue Read Chapter 11 to learn more
parame-31 D Default roles are enabled when a user connects to the database, even if the roles are
password-protected See Chapter 12 for more information
32 D DIAGNOSTIC_DEST is new to Oracle 11g, and it determines the location of the alert log
file and trace files Read Chapter 14 to learn more about alert log and trace file locations
Trang 19Answers to Administration I Assessment Test lxiii
33 B The highest level at which a user can request a lock is the table level; the only other lock
level available to a user is a row-level lock Users cannot lock at the block or schema level
Read Chapter 13 to learn more
34 C There are no standard password-complexity settings in either the initialization
param-eters or the profiles A password-verify function can validate new passwords against any rules that you can code in PL/SQL, including regular-expression comparisons See Chapter
12 for more information
35 A You can use the Undo Management Advisor to monitor and manage the undo segments
to ensure maximum levels of read consistency and minimize occurrences of “ORA-01555:
Snapshot Too Old” error messages For more information, see Chapter 14
36 B Redo log files record all the changes made to Oracle Database, whether the changes are
committed or not To learn more about redo log files and database recovery, read Chapters
15 and 16
37 B Settings such as the control file autobackup filename format and the snapshot-control
file destination filename must be configured using the RMAN command-line interface To learn more, read Chapter 15
38 D Options A and B are a lot of work The remap_datafile parameter applies only
to CREATE TABLESPACE and CREATE DIRECTORY statements, not indexes The remap_
tablespace parameter tells Data Pump import to change the tablespace that objects are stored in between the source and the target database See Chapter 17 for more information
39 D The distance between the checkpoint position in the redo log file and the end of the
redo log group can never be more than 90 percent of the size of the smallest redo log group
Read Chapter 16 to learn more about checkpoints and instance recovery
40 C If the redo log file group has never been used, the value of STATUS is UNUSED until the
log file member is used to record redo information Read Chapter 16 for more information
41 D REPLACE is the valid value; it drops the existing table and creates the table using the
definition from the dump file SKIP leaves the table untouched APPEND inserts rows to the existing table TRUNCATE leaves the structure but removes all existing rows before inserting rows See Chapter 17 to learn more
42 E To tune the instance-recovery time, configure the FAST_START_MTTR_TARGET parameter
to a nonzero value The default is 300 seconds A lower value will reduce the instance-recovery time but may cause frequent checkpoints A value of 0 turns off MTTR tuning To learn more, read Chapter 15
Trang 23Chapter
SQL FunDamentaLS I exam ObjectIveS cOvereD In thIS chapter:
Retrieving Data Using the SQL SELECT Statement
ÛÛ
List the capabilities of SQL SELECT statements
Û N
Execute a basic SELECT statement
Û N
Restricting and Sorting Data
ÛÛ
Limit the rows that are retrieved by a query
Û N
Sort the rows that are retrieved by a query
Û N
Use ampersand substitution to restrict and sort output at
Û N
runtime
Trang 24Oracle 11g is a very powerful and feature-rich relational
data-base management system (RDBMS) SQL has been adopted
by most RDBMSs for the retrieval and management of data, schema creation, and access control The American National Standards Institute (ANSI) has been refining standards for the SQL language for more than 20 years Oracle, like many other companies, has taken the ANSI standard of SQL and extended it to include much additional functionality
SQL is the basic language used to manipulate and retrieve data from the Oracle Database
11g SQL is a nonprocedural language, meaning it does not have programmatic constructs
such as loop structures PL/SQL is Oracle’s procedural extension of SQL, and SQLJ allows
embedded SQL operations in Java code The scope of the Oracle Database 11g SQL
Funda-mentals I test includes only SQL
In this chapter, I will discuss Oracle SQL fundamentals such as the various types of SQL statements, introduce SQL*Plus and a few SQL*Plus commands, and discuss SELECT
statements
You will learn how to write basic SQL statements to retrieve data from tables This will include coverage of SQL SELECT statements, which are used to query data from the database-storage structures, such as tables and views You will also learn how to limit the information retrieved and to display the results in a specific order
Exam objectives are subject to change at any time without prior notice and
at Oracle’s sole discretion Please visit Oracle’s Training and Certification website at http://education.oracle.com/pls/web_prod-plq-dad/
db_pages.getpage?p_exam_id=1Z0_051 for the most current exam objectives
SQL Fundamentals
SQL is the standard language to query and modify data as well as manage databases SQL is the common language used by programmers, database administrators, and users to access and manipulate data as well as to administer databases To get started with SQL in this chapter,
I will show how to use the sample HR schema supplied with the Oracle Database 11g.
Trang 25SQL Fundamentals 5
When you install Oracle software, you can choose the Basic Installation option and select the Create Starter Database check box This database will have the sample schemas used in this book The password you specify will be applicable to the SYS and SYSTEM accounts The account SYS is the Oracle dictionary owner, and SYSTEM is a database administrator (DBA) account Initially, the sample schemas are locked You need to log in to the database using SQL*Plus as the SYSTEM user and then unlock the account using the ALTER USER statement To unlock the HR schema, use ALTER USER
hr IDENTIFIED BY hrpassword ACCOUNT UNLOCK; Now you can log in to the database using the hr user with the password hrpassword Remember, the password is case sensitive
For detailed information on installing Oracle 11g software and creating Oracle Database 11g, please refer to the Oracle Technology Network
at www.oracle.com/technology/obe/11gr1_db/install/dbinst/
windbinst2.htm
To install the sample schemas in an existing Oracle Database 11g, please
follow the instructions in the Oracle document “Oracle Database Sample
Schemas 11g Release 1” at http://download.oracle.com/docs/cd/
B28359_01/server.111/b28328/toc.htm
Chapter 2 of the “Oracle Database Sample Schemas 11g Release 1”
man-ual on the Oracle Technology Network will provide instructions on how
to install the sample schemas using Database Configuration Assistant (DBCA) as well as running scripts The same chapter also gives you steps
to reinitialize the sample schema data
SQL statements are like plain English but with specific syntax SQL is a simple yet erful language used to create, access, and manipulate data and structures in the database
pow-SQL statements can be categorized as listed in Table 1.1
ta b L e 1.1 SQL Statement Categories
SQL Category Description
Data Manipulation Language (DML) Used to access, create, modify, or delete data in the existing structures of the database DML statements include those to
query information (SELECT), add new rows (INSERT), modify existing rows (UPDATE), delete existing rows (DELETE), perform a conditional update or insert operation (MERGE), see an execution plan of SQL (EXPLAIN PLAN), and lock a table to restrict access (LOCK TABLE) Including the SELECT statement in the DML group
is debatable within the SQL community, since does not