36.
Which operation can you not do to a table that is created with the following SQL statement?
CREATE TABLE properties
("Location" NUMBER primary key
,value NUMBER(15)
,lot varchar2(12)
,constraint positive_value check
(value > 0)
);
("Location" NUMBER primary key
,value NUMBER(15)
,lot varchar2(12)
,constraint positive_value check
(value > 0)
);
- A.Rename the primary key to properties.
- B.Insert a null into the value column.
- C.Add a column named owner.
- D.Rename the index supporting primary key to properties.
li>
E.
None of the above.
- Answer & Explanation
- Report
Answer : [E]
Explanation :
Explanation :
| You can rename both a constraint and an index to the same name as a table—they are in separate namespaces. Columns can be added, and owner is a valid column name. If the check constraint condition evaluates to FALSE, the data value will not be allowed; if the condition evaluates to either TRUE or NULL, the value is allowed. |
37.
Which of the statements is true regarding the table created with the following SQL statement?
CREATE TABLE autos
(vin VARCHAR2(64) primary key
,style VARCHAR2(15) default 'TUDOR'
,year char(4)
,make varchar2(12)
,model varchar2(30)
);
(vin VARCHAR2(64) primary key
,style VARCHAR2(15) default 'TUDOR'
,year char(4)
,make varchar2(12)
,model varchar2(30)
);
- A.MAKE is a reserved word; the CREATE TABLE will fail.
- B.The column style will always have a value.
- C.There is no index on this table.
- D.The column style can have a NULL value.
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| A default clause ensures that the column does not contain a NULL after an insert, but not after an update. MAKE is not a reserved word, and an index will be created on the primary key. |
38.
Which constraint-checking model is the default?
- A.Initially immediate and deferrable
- B.Initially immediate and not deferrable
- C.Initially deferred and not immediately
- D.Initially deferrable and not immediate
- Answer & Explanation
- Report
Answer : [B]
Explanation :
Explanation :
| Constraints can be created as deferrable and initially deferred, but deferred constraint checking is not the default. |
39.
Which statement on views is true?
- A.A view can only be on one base table, although that base table can be joined to itself.
- B.A view cannot be created with the same name and columns as the base table.
- C.Inserts into a view are not allowed.
- D.Privileges on a view can be different from those on the base table.
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| Views can be created on one or more base table. Views share the same namespace as tables and therefore cannot have the same name; columns, however, can be named the same as the base table. SELECT, INSERT, UPDATE, and DELETE are all valid operations on a view. One of the uses for a view is to hide portions of the base table, by granting different privileges to the view than the base table. |
40.
What can tablespaces be used for?
- A.To organize tables and indexes into manageable groupings
- B.To make sure that data stored in the tablespace does not change
- C.To move data from one database to another
- D.All of the above
- Answer & Explanation
- Report
Answer : [D]
Explanation :
Explanation :
| The primary use for a tablespace is to organize tables and indexes into manageable units. Some of the manageable operations that you can do to a tablespace include making it read-only or moving it from one database to another. |
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