Oracle 1Z0-051 Online Practice Questions and Exam Preparation

Oracle 1Z0-051 Online Questions & Answers

• Question 171:

  Which three statements are true about multiple-row sub queries? (Choose three.)

  A. They can contain a subquery within a sub query.
  B. They can return multiple columns as well as rows.
  C. They cannot contain a sub query within a sub query.
  D. They can return only one column but multiple rows.
  E. They can contain group functions and GROUP BY and HAVING clauses.
  F. They can contain group functions and the GROUP BY clause, but not the HAVING clause.
  A. They can contain a subquery within a sub query.
  B. They can return multiple columns as well as rows.
  E. They can contain group functions and GROUP BY and HAVING clauses.

• Question 172:

  A SELECT statement can be used to perform these three functions:

  1.

  Choose rows from a table.

  2.

  Choose columns from a table

  3.

  Bring together data that is stored in different tables by creating a link between them.

  Which set of keywords describes these capabilities?

  A. difference, projection, join
  B. selection, projection, join
  C. selection, intersection, join
  D. intersection, projection, join
  E. difference, projection, product
  B. selection, projection, join

• Question 173:

  For which action can you use the TO_DATE function?

  A. Convert any date literal to a date
  B. Convert any numeric literal to a date
  C. Convert any character literal to a date
  D. Convert any date to a character literal
  E. Format '10-JAN-99' to `January 10 1999'
  C. Convert any character literal to a date

• Question 174:

  Which two statements are true regarding single row functions? (Choose two.)

  A. They can be nested only to two levels
  B. They always return a single result row for every row of a queried table
  C. Arguments can only be column values or constant
  D. They can return a data type value different from the one that is referenced
  E. They accept only a single argument
  B. They always return a single result row for every row of a queried table
  D. They can return a data type value different from the one that is referenced

• Question 175:

  Which is the valid CREATE [TABLE statement?

  A. CREATE TABLE emp9$# (emp_no NUMBER(4));
  B. CREATE TABLE 9emp$# (emp_no NUMBER(4));
  C. CREATE TABLE emp*123 (emp_no NUMBER(4));
  D. CREATE TABLE emp9$# (emp_no NUMBER(4). date DATE);
  A. CREATE TABLE emp9$# (emp_no NUMBER(4));

• Question 176:

  Which statement adds a constraint that ensures the CUSTOMER_NAME column of the CUSTOMERS table holds a value?

  A. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
  B. ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
  C. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;
  D. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;
  E. ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;
  F. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;
  C. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;

• Question 177:

  Which three are true? (Choose three.)

  A. A MERGE statement is used to merge the data of one table with data from another.
  B. A MERGE statement replaces the data of one table with that of another.
  C. A MERGE statement can be used to insert new rows into a table.
  D. A MERGE statement can be used to update existing rows in a table.
  A. A MERGE statement is used to merge the data of one table with data from another.
  C. A MERGE statement can be used to insert new rows into a table.
  D. A MERGE statement can be used to update existing rows in a table.

• Question 178:

  Evaluate the following SQL statement:

  

  Which statement is true regarding the outcome of the above query?

  A. It produces an error because the ORDER BY clause should appear only at the end of a compound query-that is, with the last SELECT statement
  B. It executes successfully and displays rows in the descending order of PROMO_CATEGORY
  C. It executes successfully but ignores the ORDER BY clause because it is not located at the end of the compound statement
  D. It produces an error because positional notation cannot be used in the ORDER BY clause with SET operators
  A. It produces an error because the ORDER BY clause should appear only at the end of a compound query-that is, with the last SELECT statement

• Question 179:

  Examine the structure of the CUSTOMERS table:

  

  CUSTNO is the PRIMARY KEY in the table. You want to find out if any customers' details have been entered more than once using different CUSTNO, by listing all the duplicate names. Which two methods can you use to get the required result? (Choose two.)

  A. self-join
  B. subquery
  C. full outer-join with self-join
  D. left outer-join with self-join
  E. right outer-join with self-join
  A. self-join
  B. subquery

• Question 180:

  Examine this statement:

  SELECT student_id, gpa FROM student_grades WHERE gpa > andandvalue;

  You run the statement once, and when prompted you enter a value of 2.0. A report is produced.

  What happens when you run the statement a second time?

  A. An error is returned.
  B. You are prompted to enter a new value.
  C. A report is produced that matches the first report produced.
  D. You are asked whether you want a new value or if you want to run the report based on the previous value.
  C. A report is produced that matches the first report produced.