人間の性格を理解する：練習問題

The PRODUCT_INFORMATION table has a UNIT_PRICE column of data type NUMBER(8,2). Evaluate this SQL statement: SELECT TO_CHAR(unit_price, ‘$9,999’) FROM product_information; Which two statements are true about the output?. A row whose UNIT_PRICE column contains the value 10235.99 will be displayed as $1,0236. A row whose UNIT_PRICE column contains the value 1023.99 will be displayed as $1,023. A row whose UNIT_PRICE column contains the value 10235.99 will be displayed as #######. A row whose UNIT_PRICE column contains the value 10235.99 will be displayed as $1,023. A row whose UNIT_PRICE column contains the value 1023.99 will be displayed as $1,024.

Examine this query: SELECT employee_id, first_name, salary FROM employees WHERE hire_date > ‘&1’; Which two methods should you use to prevent prompting for a hire date value when this query is executed?. Use the DEFINE command before executing the query. Store the query in a script and pass the substitution value the script when executing it. Execute the SET VERIFY OFF command before executing the query. Use the UNDEFINE command before executing the query. Replace ‘&1’ with ‘&&1’ in the query. Execute the SET VERIFY ON command before executing the query.

DATADIR1 and DATADIR2 are database directory objects. Examine this command: [oracle@host01 ~] expdp system/oracle \ > FULL=y \ > DUMPFILE=datadir1:full%U.dmp, datadir2:full%U.dmp \ > FILESIZE=2G \ > PARALLEL=4 \ > LOGFILE=datadir1:/expfull.log \ > JOB_NAME=expfull Which two statements are true about the expdp operation?. It creates dump files for the entire database. It fails if the total size of the dump file is more than 2 GB. It creates a master table to store details of the export operation. It starts only when four worker processes are available. It creates dump files only for objects in the SYSTEM schema.

Which three statements are true about UNDO and REDO?. UNDO is used for some flashback operations. REDO is used for ROLLBACK. Both REDO and UNDO can be multiplexed. REDO is used for read consistency. REDO is used for instance recovery. UNDO is used for read consistency.

Which two statements are true about a full outer join?. It returns and unmatched rows from both tables being joined. It includes rows that are returned by a Cartesian product. It returns only unmatched rows from both tables being joined. The Oracle join operator (+) must be used on both sides of the join condition in the WHERE clause. It includes rows that are returned by an inner join.

Which two tasks can be performed in the NOMOUNT state?. Re-creating control files. Renaming data files. Creating a database. Enabling online redo log archiving. Full database recovery.

Which three statements are true about roles?. The SET ROLE statement can disable one or more roles for a session. Object privileges may not be granted to roles. Roles must be password protected. Roles may be granted to roles. All roles granted to a user set on by default when the user logs in. The SET ROLE statement can enable one or more roles for a session.

Examine the description of the PRODUCTS table: Name Null? Type ---------------------------- ---------- -------------------- PRODUCT_ID NOT NULL NUMBER(2) PRODUCT_NAME VARCHAR(10) UNIT_PRICE NUMBER(3) SURCHARGE VARCHAR2(2) EXPIRY_DATE DATE DELIVERY_DATE DATE Which three queries use valid expressions?. SELECT product_id, unit_price, unit_price + surcharge FROM products;. SELECT product_id, (expiry_date – delivery_date) * 2 FROM products;. SELECT product_id, unit_price || 5 “Discount”, unit_price + surcharge - discount FROM products;. SELECT product_id, unit_price, 5 “Discount”, unit_price + surcharge - discount FROM products;. SELECT product_id, expiry_date * 2 FROM products;. SELECT product_id, (unit_price * 0.15 / (4.75 + 522.25)) FROM products;.

Which three statements are true about an SPFILE?. It must exist for a database instance to start. It can be used to create a pfile. It can be created by SYS from an idle instance. It contains initialization parameters whose values can be changed using the ALTER SYSTEM command. It contains only static initialization parameters.

Examine the data in the CUST_NAME column of the CUSTOMERS table: CUST_NAME ------------- Renske Ladwig Jason Mallin Samuel McCain Allan MCEwen Irene Mikkilineni Julia Nayer You want to display the CUST_NAME values where the last name starts with Mc or MC. Which two WHERE clauses give the required result?. WHERE INITCAP(SUBSTR(cust_name, INSTR(cust_name, ‘ ’) + 1)) IN (‘MC%’, ‘Mc%’). WHERE UPPER(SUBSTR(cust_name, INSTR(cust_name, ‘ ’) + 1)) LIKE UPPER (‘MC%’). WHERE SUBSTR(cust_name, INSTR(cust_name, ‘ ’) + 1) LIKE ‘Mc%’ OR ‘MC%’. WHERE SUBSTR(cust_name, INSTR(cust_name, ‘ ’) + 1) LIKE ‘Mc%’. WHERE INITCAP(SUBSTR(cust_name, INSTR(cust_name, ‘ ’) + 1)) LIKE ‘Mc%’.

Which three statements are true about Enterprise Manager Cloud Control?. It uses a web-based console built into the Oracle database using XML DB. It is available to manage a database only when that database is open. It provides management for Oracle middleware. It is integrated with My Oracle Support. It provides management for Oracle-engineered systems.

Which three are benefits of using temp UNDO when performing DML on Global temporary tables?. It reduces the amount of UNDO stored in the UNDO tablespace. It reduces I/Os to the SYSTEM tablespace. It reduces the amount of redo generated. It permits DML on Global temporary tables even if the database is opened read only. It reduces I/Os to the SYSAUX tablespace.

Which three statements are true about multiple row subqueries?. They can return multiple columns. They can contain HAVING clauses. They cannot contain a subquery. They can contain GROUP BY clauses. Two or more values are always returned from the subquery.

Which two statements are true about unexpired undo?. It consists of UNDO only for uncommitted transactions. It is required when a transaction issues a ROLLBACK statement. It may be used to support flashback queries. It is the first type of UNDO overwritten when trying to avoid out-of-space errors. It is retained if possible for the time specified in UNDO_RETENTION.

Which three tasks are performed by background processes in an Oracle database instance?. Writing dirty database block images from the buffer cache. Writing redo to log files. Reading database blocks into the buffer cache. Registering services with Oracle Net listeners. Creating dedicated server connections.

Which three statements are true about views in an Oracle Database?. Views can join tables only if they belong to the same schema. A view can be created that refers to a non-existent table in its defining query. Views have no segment. Rows inserted into a table using a view retained in the table if the view is dropped. A SELECT statement cannot contain a WHERE clause when querying a view containing a WHERE clause in its defining query. Views have no object number.

You issued this command: DROP TABLE hr.employees; Which three statements are true?. All constraints defined on HR.EMPLOYEES are dropped. All indexes defined on HR.EMPLOYEES are dropped. Synonyms for HR.EMPLOYEES are dropped. The HR.EMPLOYEES table may be moved to the recycle bin. Views referencing HR.EMPLOYEES are dropped. Sequences used to populate columns in the HR.EMPLOYEES table are dropped.

Which two statements are true about constraints?. A PRIMARY KEY constraint can only be added to an empty table. A UNIQUE constraint can use a pre-existing index on the constrained column or columns. A CHECK constraint can refer to values in other rows. A FOREIGN KEY column can contain NULLS. A column can have only one CHECK constraint.

Examine these SQL statements which execute successfully: CREATE TABLE emp (emp_no NUMBER(2) CONSTRAINT emp_emp_no_pk PRIMARY KEY, ename VARCHAR2(15), salary NUMBER(8,2), mgr_no NUMBER(2)); ALTER TABLE emp ADD CONSTRAINT emp_mgr_fk FOREIGN KEY (mgr_no) REFERENCES emp(emp_no) ON DELETE SET NULL; ALTER TABLE emp DISABLE CONSTRAINT emp_emp_no_pk CASCADE; ALTER TABLE emp ENABLE CONSTRAINT emp_emp_no_pk; Which two statements are true after execution?. The primary key constraint will be enabled and DEFERRED. The foreign key constraint will be disabled. The foreign key constraint will be enabled and IMMEDIATE. The primary key constraint will be enabled and IMMEDIATE. The foreign key constraint will be enabled and DEFERRED.

Examine the structure of the two tables: PRODUCTS: Name Null? Type ------------- -------- ---------------- PROD_ID CHAR(2) PROD_NAME CHAR(4) EXP_DATE TIMESTAMP(6) NEW_PRODUCTS: Name Null? Type ------------- -------- ---------------- PROD_ID CHAR(4) PROD_NAME VARCHAR2(10) EXP_DATE DATE Which two queries execute successfully?. SELECT * FROM products MINUS SELECT prod_id FROM new_products;. SELECT prod_id, prod_name FROM products INTERSECT SELECT 100, prod_name FROM new_products;. SELECT prod_id FROM products UNION ALL SELECT prod_id, prod_name FROM new_products;. SELECT prod_id, exp_date FROM products UNION ALL SELECT prod_id, NULL FROM new_products;. SELECT * FROM products UNION SELECT * FROM new_products;.