1Z0-071 Exam Dumps and Practice Questions

In Oracle SQL, when performing a JOIN operation, the ON clause is used to specify the condition that relates the two tables being joined. The WHERE clause can be used to further filter the result set.

A) This is a valid join condition using the WHERE clause to filter the rows after the join has been made.

B) This statement will fail because the ON clause should only contain conditions that relate the two tables. The condition for filtering the departments table should be in the WHERE clause, not in the ON clause. This is a common mistake when writing JOIN statements.

C) This is a correct statement. The ON clause specifies how the tables are related and the WHERE clause specifies an additional filtering condition for the query.

D) This statement is also correct. It's similar to the first statement (A) and properly places the department_id filter in the ON clause, which is acceptable though not typically best practice as it can be less readable than using a WHERE clause for non-join conditions.

When the JOIN operation is executed, the database first pairs rows from the joined tables that meet the join condition specified by the ON clause. Then, it filters the result of the JOIN operation based on the condition specified in the WHERE clause.

Oracle Documentation on Joins: https://docs.oracle.com/database/121/SQLRF/queries006.htm#SQLRF52359

A . Correct. Truncating a table, especially in another schema, requires the ALTER ANY TABLE or DROP ANY TABLE system privilege. B. Correct. Accessing external files through the database involves the CREATE ANY DIRECTORY privilege, which is a system privilege. C. Correct. Creating a session in a database, which is required to log in, necessitates the CREATE SESSION system privilege. D. Incorrect. Querying any table is an object privilege, which can be granted by the owner of the table. E. Incorrect. The WITH GRANT OPTION clause is used with object privileges, not system privileges. F. Incorrect. Executing a procedure in another schema requires the EXECUTE object privilege on that procedure.

Oracle Database Security Guide provides the details about system privileges necessary for these actions.

C: True. A SQL statement may include multiple single row subqueries in different parts of the statement, such as in the SELECT list, WHERE clause, or HAVING clause. Each subquery must independently satisfy the requirement of returning a single row to avoid runtime errors.

D: True. Single row subqueries can be used in the HAVING clause. This allows for filtering groups based on conditions evaluated against individual or aggregated values returned by the subquery. The subquery must return a single value to be valid in this context.

E: True. Single row subqueries are often placed on the right side of the comparison operator in a SQL condition. This positioning is typical because the left side often references a column or an expression related to the main query, while the subquery on the right side dynamically provides a value for comparison.

B: True. Multiple table insert statements, specifically the conditional INSERT ALL, can transform a single row from the source table into multiple rows in one or more target tables depending on the conditions specified in the WHEN clauses.

E: True. The unconditional INSERT ALL statement will insert rows into multiple target tables without any conditions. However, it does not require the same number of columns in both the source and target tables. The INSERT ALL syntax allows you to specify different columns for each target table into which rows will be inserted.

Multiple table insert operations allow for complex insert scenarios, where based on the data, one can insert into different tables or multiple times into the same table based on different conditions.

Reference: Oracle SQL reference details the use of INSERT ALL and INSERT FIRST clauses for inserting into multiple tables based on conditions specified.

Global temporary tables in Oracle Database are designed to hold temporary data for the duration of a session or a transaction.

Given that the global temporary table is created and then populated twice from the emp table without any mention of data deletion, one would initially think the count would be 28, since 14 rows are inserted twice. However, if the temporary table was created with the default ON COMMIT DELETE ROWS option, the rows are deleted at the end of the transaction, which is signified by the COMMIT operation.

Thus, after the first COMMIT, the temporary table would be empty. After the second INSERT, another 14 rows would be added. So, the last query would retrieve 14 rows unless a DELETE operation was committed.

Oracle Documentation on Temporary Tables: https://docs.oracle.com/cd/B28359_01/server.111/b28310/tables003.htm#ADMIN11633

Please note that the actual number of rows retrieved by the last query could differ if there are any triggers, cascading deletes, or the table is defined differently than assumed in this context.