1z0-071 Exam Dumps : Oracle Database 12c SQL

For the SELECT statement from two tables without a JOIN clause:

Option B: You can add a WHERE clause with filtering criteria.

A WHERE clause can be added to a query to filter the results based on specified conditions.

Option E: It returns the same rows as SELECT * FROM bricks CROSS JOIN colors.

A comma-separated list of tables in a FROM clause is equivalent to a CROSS JOIN, resulting in a Cartesian product of the tables.

Options A, C, and D are incorrect because:

Option A: You cannot add an ON clause without changing the comma-separated FROM clause to a proper JOIN.

Option C: It returns the Cartesian product, not the sum, of the rows from BRICKS and COLORS.

Option D: A USING clause is not applicable without changing the syntax to a proper JOIN.

Based on the table structure given in the image, to return the value 'CUBE' from the 'bricks' table when joined with 'boxes', the condition must ensure that the weight of the bricks is within the allowed weight range specified in the 'boxes' table for a 'SMALL' box size.

A. True. Since MAX_WEIGHT is 0, a comparison using >= min_weight AND weight < max_weight will only return rows where the weight is less than 0, which is impossible for actual weight values, suggesting there might be a mistake in the data provided or the comparison logic.

E. True. NOT (weight > max_weight) effectively translates to 'where weight is less than or equal to max_weight'. However, since MAX_WEIGHT is 0, this condition would only be true if the weight is not greater than 0, which can only happen if the weight is 0 or less. This seems to indicate an anomaly where either the data is incorrect, or the condition is meant to handle a case where the weight is zero or possibly a negative placeholder value.

Both B and D will potentially return more than just 'CUBE' if there are bricks with weights greater than MIN_WEIGHT. C is incorrect because BETWEEN is inclusive, and there are no weights that are both greater than or equal to MIN_WEIGHT and less than or equal to MAX_WEIGHT when MAX_WEIGHT is 0.

Regarding the use of SAVEPOINT in transactions:

C. A SAVEPOINT does not issue a COMMIT: A SAVEPOINT in Oracle SQL is used to mark a point within a transaction. It does not commit the transaction; rather, it allows partial rollbacks to the point of the SAVEPOINT without affecting other uncommitted changes outside it.

E. Rolling back to a SAVEPOINT can undo a DELETE statement: SAVEPOINT allows you to rollback DML changes like INSERT, UPDATE, and DELETE that occur after the SAVEPOINT was established, but before a COMMIT.

Incorrect options:

A: CREATE INDEX is a DDL statement, and like most DDL statements, it implicitly commits the transaction, making it impossible to rollback using a SAVEPOINT.

B: Multiple SAVEPOINTS can be defined within a single transaction, each with unique or reused names.

D: TRUNCATE is a DDL statement that also implicitly commits the transaction; hence it cannot be rolled back to a SAVEPOINT.