Oracle 1z0-071 Online Access

Regarding creating tables in an Oracle database:

B. The same table name can be used for tables in different schemas: In Oracle, a schema is essentially a namespace within the database; thus, the same table name can exist in different schemas without conflict, as each schema is distinct.

C. A system privilege is required: To create tables, a user must have the necessary system privileges, typically granted explicitly or through roles such as CREATE TABLE or administrative privileges depending on the environment setup.

Incorrect options for all three repeated questions:

A: Oracle SQL does not allow specifying the maximum number of rows directly in a CREATE TABLE statement; this is controlled by storage allocation and database design rather than table creation syntax.

D: Creating an external table does not create the physical file. It merely creates a table structure that allows access to data stored in an external file specified in the directory; the file itself must already exist or be managed outside of Oracle.

E: A primary key constraint is not mandatory for creating tables. While it is a common practice to define a primary key to enforce entity integrity, it is not required by the Oracle SQL syntax for table creation.

These answers and explanations are aligned with Oracle Database 12c SQL documentation and standard practices.

The Oracle Data Pump access driver allows for specific actions with external tables:

B. Read data from an external table and load it into a table in the database. Data Pump can be used to efficiently transfer data between external tables and internal database tables.

C. Query data from an external table. The Data Pump access driver supports querying data directly from external tables.

F. Read data from a table in the database and insert it into an external table. The Data Pump can also export data from database tables to external table formats.

Options A, D, and E are incorrect:

A and D are incorrect as the creation of a directory object is not specific to the Data Pump access driver but is a general external table requirement.

E is incorrect because DML operations directly on external tables are not supported; they are read-only.

A. True. The DECODE function can evaluate conditions, but it is limited to equality checks. On the other hand, CASE can evaluate these and a broader range of conditions using different comparison operators.

D. True. DECODE is a function in Oracle SQL that allows for simple conditional query transformation. CASE is not a function but a statement that provides more flexibility and readability when handling conditional logic in SQL queries.

DECODE is more limited compared to CASE since it can't perform logical operations other than equality.

To calculate the date from a given base date with intervals, Oracle allows you to add or subtract intervals from dates. Since the NLS_DATE_FORMAT is set to DD-MM-YYYY, the output is expected to be in that format.

Option B seems to calculate a date that is 3 months and 7 days ahead of October 29, 2019, and then subtracts 360 seconds (which is 6 minutes), resulting in a time that is still within the same day.

Here's how the calculation in option B would work out:

Start date: 29-10-2019

Add 3 months: 29-01-2020

Add 7 days: 05-02-2020

Subtract 360 seconds: Since it's only a few minutes, the date remains 05-02-2020.

However, this does not match the provided result of 02-JAN-2020. We would need to consider the exact amount of time being subtracted or added to find the correct answer.

But upon reviewing the options, they all have various syntax errors such as a missing TO_CHAR function, incorrect quotes, and date formats not matching the session's NLS_DATE_FORMAT. Therefore, we would need to correct these issues to find the right answer.