READ Free Dumps For Oracle- 1z0-007
| Question ID 7949 | In which scenario would TOP N analysis be the best solution?
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| Option A | You want to identify the most senior employee in the company.
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| Option B | You want to find the manager supervising the largest number of employees.
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| Option C | You want to identify the person who makes the highest salary for all employees.
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| Option D | You want to rank the top three sales representatives who have sold the maximum number of products.
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| Correct Answer | D |
Explanation Explanation/Reference: Explanation: If you want to rank the top three sales representatives who have sold the maximum number of products TOP-N query will be the best solution. TON-N queries use inline views and are handy for displaying a short list of table data, based on "greatest" or "least" criteria. Incorrect Answers A: To complete this request you don't need to use TOP-N query. B: It is not necessary to use TOP-N query in this case. C: To complete this request you don't need to use TOP-N query. OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 162-165 Chapter 4: Subqueries
| Question ID 7950 | Which constraint can be defines only at the column level?
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| Option A | UNIQUE
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| Option B | NOT NULL
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| Option C | CHECK
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| Option D | PRIMARY KEY
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| Option E | FOREIGN KEY
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| Correct Answer | B |
Explanation Explanation/Reference: Explanation: The NOT NULL constraint can be defined only at the column level. It enforces that a value must be defined for this column such that the column may not be NULL for any row. Incorrect Answers A: The UNIQUE constraint enforces uniqueness on values in the constrained column. It can be defined not only at the column level. C: The CHECK constraint enforces that values added to the constrained column must be present in a static list of values permitted for the column. D: The PRIMARY KEY constraint stipulates that values in the constrained column(s) must be unique and not NULL. If the primary key applies to multiple columns, then the combination of values in the columns must be unique and not NULL. E: The FOREIGN KEY constraint enforces that only values in the primary key of a parent table may be included as values in the constrained column(s) of the child table. OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 227-232 Chapter 5: Creating Oracle Database Objects