Oracle 1z0-071 Exam Made Easy: Step-by-Step Preparation Guide

Regarding valid INSERT statements into the ORDERS table:

B. This is a valid statement because it uses TO_DATE for potentially setting a NULL date and provides defaults implicitly where not specified, adhering to the column constraints and requirements.

D. This statement is correctly formatted and provides values for non-optional fields, using DEFAULT implicitly for unspecified optional fields.

Incorrect options:

A: The subquery format and values provided do not match the expected column count and types for direct insert.

C: Incorrect format due to an improper string for the ORDER_MODE and possibly incomplete values.

E: Incorrect syntax; DEFAULT should be correctly capitalized, and the value order and type must match the table structure.

The data dictionary contains metadata (data about data) about the database and its objects.

A. False. DBA_ views display metadata for objects accessible to the database administrator, not only for the SYS schema.

B. True. ALL_ views display information about all the objects that the current user has access to. This does not necessarily mean the user has privileges on these objects, only that the user can see them.

C. False. The data dictionary is not accessible when the database is closed because it requires the database to be open in order to access the system tables.

D. True. Not all types of metadata are available in all three prefixes (ALL_, DBA_, USER_). Some specific metadata might only be available in one or two of these view types.

E. False. The data dictionary stores metadata in tables. The various views (ALL_, DBA_, USER_, etc.) provide different perspectives on this data.

References:

Oracle Documentation on Data Dictionary and Dynamic Performance Views: https://docs.oracle.com/cd/B28359_01/server.111/b28310/datadict.htm

In Oracle SQL, when using the set operators like MINUS, the number of columns and their data types in the SELECT statements must match in sequence.

A. This query will not execute successfully because the SELECT * FROM bricks_stage will return all columns from the BRICKS_STAGE table, which are WEIGHT, SHAPE, and COLOR, but the first SELECT statement specifies only SHAPE and COLOR. The order and number of columns must match.

B. This query will not execute successfully. The SELECT statements have a different number of columns, and the data types of the columns in the same positions do not match between the two queries. The first column in the first SELECT is SHAPE (VARCHAR2), and in the second SELECT, it is WEIGHT (NUMBER).

C. This query will execute successfully. The SELECT * from both tables will ensure that the number of columns and their data types are the same, as SELECT * selects all columns from the table. As long as the two tables have the same column order and data types for those columns, the query will execute.

D. This query will not execute successfully. Even though the columns are of the same data types, their order in the SELECT statements must match for the set operator to work. The order of SHAPE and COLOR is switched between the two queries.

E. This query will not execute successfully. The number of columns in the SELECT statements is the same, but their data types do not match between the two queries. BRICK_ID (NUMBER) in the first query does not match WEIGHT (NUMBER) in the second, and SHAPE (VARCHAR2) does not match COLOR (VARCHAR2).

References:

Oracle Database SQL Language Reference, 12c Release 1 (12.1): "Combining Queries with Set Operators"

Oracle Database SQL Language Reference, 12c Release 1 (12.1): "MINUS"

C. True, when performing a self join, aliases are used to differentiate the same table in different contexts within the same query. This helps in comparing different rows within the same table as if they were in two separate tables.D. True, the ON clause can be used in self joins to specify the conditions on which the join is based. This is a standard method for specifying join conditions in SQL.F. True, a self join can be an outer join, allowing for the inclusion of rows that do not have a matching row in the same table according to the join condition. This enhances the flexibility of data analysis and reporting.

References:

Oracle documentation on joins: Oracle Database SQL Language Reference

Details on self joins and outer joins: Oracle Joins Tutorial

To achieve the desired output for the query from the MEMBERS table:

C. ORDER BY 1, LNAME DESC: This clause correctly sorts the results first by the first column (city) in ascending order by default, and then by the alias LNAME (last_name) in descending order.

E. WHERE city LIKE '%AN%': This clause correctly filters the rows to include only those cities containing the string 'AN' anywhere in the city name, using the LIKE operator which is suitable for pattern matching.

Incorrect options:

A: This would order both columns in ascending order, which does not meet the requirement for last_name to be in descending order.

B: This misplaces the order priorities and uses explicit column names that contradict the sorting requirement specified.

D: Incorrect syntax for a LIKE clause; equality operator cannot be used with wildcards.

F: The IN operator is incorrectly used here with a pattern, which is not valid syntax.

The query uses two functions: ROUND and TRUNC. The ROUND function will round the number 156.00 to the nearest hundred because of the -2 which specifies the number of decimal places to round to. This will result in 200. Then the TRUNC function truncates this number to the nearest 10, due to the -1 argument, which will give us 200 as the result since truncation does not change the rounded value in this case.

A. 16 (Incorrect)

B. 160 (Incorrect)

C. 150 (Incorrect)

D. 200 (Incorrect)

E. 100 (Incorrect)

D: True. A BLOB (Binary Large Object) is used to store unstructured binary data within the Oracle Database. It can hold a variable amount of data.

F: True. A BFILE is a datatype in Oracle SQL used to store a locator (pointer) that points to binary data stored in operating system files outside of the Oracle Database.

Both BLOB and BFILE are used for large binary data but differ in where the data is actually stored - BLOB stores the data inside the Oracle Database, whereas BFILE stores the data in the file system outside the database.

References:The Oracle Database SQL Language Reference guide details the characteristics and uses of BLOB and BFILE datatypes among others, describing their storage characteristics and data type definitions.

The CHECK constraint is generally used to limit the range of values that can be placed in a column. If a CHECK constraint exists on the department_id to only allow values such as 80 (assuming from the context provided):

A. UPDATE emp80 SET department_id=90 WHERE department_id=80: This UPDATE statement attempts to set the department_id to 90 for rows where it is currently 80. If there is a CHECK constraint preventing department_id from being anything other than 80, this statement would violate that constraint.

Incorrect options:

B: DELETE operations do not affect CHECK constraints as they do not involve modifying or setting column values.

C and D: SELECT statements do not modify data and thus cannot violate data integrity constraints like CHECK constraints.

A. Correct. Foreign key constraints can be nullable. This allows the possibility of a row not having a link to another table. B. Incorrect. Unique key constraints do not allow multiple rows to have null values unless the constraint is defined on multiple columns. C. Incorrect. Primary key columns must be NOT NULL and unique across the table. D. Incorrect. Primary or unique key values do not refer to foreign keys; it's the foreign keys that refer to primary or unique keys. E. Correct. Foreign key constraints enforce referential integrity by requiring that each foreign key value matches a primary or unique key value in the related table.

These are standard rules in relational databases, which can be confirmed in the Oracle Database Concepts Guide.

The requirements specify that we need to select book titles based on a price condition and a date condition, and then sort the results by the date of purchase.

A. This query will not execute successfully because there is a syntax error in the price condition. It should be price < 500 OR price > 1000.

B. This query is incorrect. The requirement specifies that the price must be less than 500 or more than 1000, not in a list of values.

C. This query is correct. It selects books where the price is not between 500 and 1000 (thus, less than 500 or more than 1000) and the purchase date is before January 17, 2007, ordered by purchase date in descending order.

D. This query is incorrect because it selects books with prices between 500 and 1000, which is not what the requirement specifies.