Oracle 12c: SQL - Chapter 6

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Based on the structure of the BOOKS table, which of the following is a valid SQL statement?

CREATE INDEX books_title_idx ON books (INITCAP(title));​

Which of the following commands is used to create a function-based index?

CREATE INDEX...ON

The last value generated by a sequence is stored in the ____ pseudocolumn.

CURRVAL​

A column has low cardinality if it contains many distinct values.

False

A large table containing a particular column that is frequently referenced by a WHERE clause would probably benefit from a(n) sequence .

False

A sequence serves as a nickname for a database object.

False

A(n) *index* can be used to generate a series of unique numbers.

False

All synonyms are PUBLIC.

False

An index is implicitly created when a NOT NULL constraint is added to a table.

False

An index is implicitly created whenever a(n) *CHECK* constraint is created for a table column.

False

The *GENERATE* option can be used to have a sequence pre-generate a set of numbers before they are requested by a user.

False

The NEXTVALUE pseudocolumn is used to actually generate the next value in a sequence.

False

The USER_ALL data dictionary view displays information about all the relevant objects owned by the user.

False

The USER_SEQ data dictionary view can be used to verify sequence settings.

False

The default value for the INCREMENT BY clause is two .

False

The ____ clause is used to specify the interval between two sequential values.

INCREMENT BY

Which of the following is a pseudocolumn?

NEXTVAL

An index is not implicitly created when which type of constraint is created?

NOT NULL

A sequence value may be set as a DEFAULT value for a column.

True

A(n) *index* can be used to quickly determine whether a value already exists in a specific column.

True

A(n) index can be created based on more than one column.

True

A(n) sequence can be used to generate a series of numeric values.

True

An explicitly created index can be dropped with the DROP INDEX command.

True

If the minimum value for a sequence is not specified, then NOMINVALUE will be assumed as the default.

True

The NEXTVAL pseudocolumn can be referenced in an INSERT command to add the value to a database table.

True

The START WITH clause of a sequence cannot be reset with the ALTER SEQUENCE command.

True

The USER_INDEXES data dictionary view can be used to verify existing indexes.

True

The default beginning value for a sequence is *one*.

True

The highest possible value for a descending sequence is -1.

True

To change the starting value for a sequence, the sequence must be dropped and then re-created.

True

When a positive value is assigned to the INCREMENT BY clause of the CREATE SEQUENCE command, numeric values are generated in ascending order.

True

Which of the following is a valid SQL statement when referencing a sequence?

none of the above

Which of the following can be created so other users will not need to prefix a table owned by user Jeff with his schema name?

synonym

Which of the following is not a valid statement concerning identity columns.

​A DEFAULT clause may be assigned

Which of the following is a correct statement?

​A PUBLIC synonym can be referenced by any user.

Which option is used to have Oracle12c pre-generate a set of values and store those values in the server's memory?

​CACHE

Which command will create an index?

​CREATE INDEX indexname ON tablename (columnname)

Which command will create a sequence named NEWSEQUENCE to generate a series of integers?

​CREATE SEQUENCE newsequence;

Which command will create a synonym for a table?

​CREATE SYNONYM synonymname FOR tablename;

Which of the following commands can be used to remove a sequence from a database?

​DROP SEQUENCE

Which of the following is used to establish a minimum or maximum value, respectively, for a sequence?

​MINVALUE | MAXVALUE

Which of the following statements about NEXTVAL and CURRVAL is incorrect?

​NEXTVAL and CURRVAL are pseudocolumns that store unique names for database objects.

To remove a PUBLIC synonym, you must include the ____ keyword in the DROP command.

​PUBLIC

Which of the following sequence settings cannot be changed with the ALTER SEQUENCE command?

​START WITH

When working with cached sequence values, which of the following is correct?

​When a value has been generated and cached, that value has been assigned and cannot be regenerated until the sequence begins a new cycle.

An index can be created ____.

​both a and b

Which of the following contains the ROWID of referenced rows?

​index

Which of the following commands can be used to modify an index?

​none of the above

Which of the following is defined in Oracle12 as simply anything that has a name and a defined structure?

​object

A(n) ____ synonym is used by an individual to reference objects owned by that person.

​private


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