Oracle 1Z0-515 Online Practice Questions and Exam Preparation

Oracle 1Z0-515 Online Questions & Answers

• Question 31:

  Your customer wants to use Database Resource Manager to help ensure consistent performance based on users and operations. In designing this implementation, which limitation CANNOT be imposed through Database Resource Manager?

  A. Specifying the maximum number of concurrent operations for a resource group
  B. Limiting resource consumption for a resource group
  C. Specifying the amount of parallelism for a resource group
  D. Limiting access to particular data for a resource group
  D. Limiting access to particular data for a resource group

• Question 32:

  Identify the action that you CANNOT perform using Database Resource Manager.

  A. Define Consumer Groups.
  B. Create rules to map sessions to Consumer Groups.
  C. Define a Resource Plan.
  D. Allocate individual CPUs to Consumer Groups.
  D. Allocate individual CPUs to Consumer Groups.

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  Oracle Database Resource Management (DRM) provides tools that allow any Oracle DBA to manage a database server's CPU resources effectively for application user groups and during different resource demand periods.

  DRM consists of four basic components:

  *Resource Consumer Groups (not A). A resource consumer group is a collection of users with similar requirements for resource consumption. Users can be assigned to more than one resource consumer group, but each user's active session

  can only be assigned to one resource consumer group at a time. *Resource Plans (not C). In its simplest form, a resource plan describes the resources allocated to one or more resource consumer group(s).

  *Resource Plan Directives (not B). Resource plan directives allocate resources among the resource consumer groups in the resource plan. Essentially, directives connect resource consumer groups or subplans to their resource plans.

  * SYSTEM_PLAN. Oracle supplies an initial, default resource plan named SYSTEM_PLAN. This plan implements a CPU utilization resource allocation method to divide and prioritize CPU resources to three resource consumer groups

• Question 33:

  Which two statements are true about the advantages of using a data warehouse?

  A. A data warehouse uses fewer database structures, so access to answers is faster and easier
  B. A data warehouse is typically implemented with a different design, making access faster.
  C. A data warehouse is optimized for ongoing write activity, making response faster.
  D. A data warehouse uses specialized features of the Oracle database, like materialized views and star transformations, making response faster.
  B. A data warehouse is typically implemented with a different design, making access faster.
  D. A data warehouse uses specialized features of the Oracle database, like materialized views and star transformations, making response faster.

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  Data warehouses often use denormalized or partially denormalized schemas (such as a star schema) to optimize query performance.

  Note: A materialized view is a pre-computed table comprising aggregated or joined data from fact and possibly dimension tables. Also known as a summary or aggregate table.

• Question 34:

  Exadata uses smart scans, which are executed in________.

  A. Exadata Storage Server cells
  B. Database Server node memory
  C. Database Server node CPUs
  D. Exadata does not use smart scans.
  A. Exadata Storage Server cells

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  The Oracle Exadata Database Machine brings database performance to a whole new level, but have you ever wondered what exactly makes it so fast? Several components of the Oracle Exadata Database Machine, such as Oracle Database 11g Release 2; Oracle Exadata's Smart Flash Cache, Hybrid Columnar Compression, and SmartScan features; and InfiniBand interconnect, help deliver high performance. One of the key technologies that supports this performance is the storage index, which is not a regular database index. Storage indexes reside in the memory of the storage servers--also called storage cells--and significantly reduce unnecessary I/O by excluding irrelevant database blocks in the storage cells.

  Oracle Exadata I/O and Smart Scan Storage in Oracle Exadata changes query processing so that not all blocks have to go to the database server for that server to determine which rows might satisfy a query. Oracle Exadata's Smart Scan feature enables certain types of query processing to be done in the storage cell. With Smart Scan technology, the database nodes send query details to the storage cells via a protocol known as iDB (Intelligent Database). With this information, the storage cells can take over a large portion of the data- intensive query processing. Oracle Exadata storage cells can search storage disks with added intelligence about the query and send only the relevant bytes, not all the database blocks, to the database nodes--hence the term smart scan.

• Question 35:

  Data Guard compresses data:

  A. Always
  B. When using logical standby
  C. When using physical standby
  D. When catching up after a network failure
  C. When using physical standby

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  A Physical standby database replicates the exact contents of its primary database across the Oracle Net network layer. While the physical storage locations can be different, the data in the database will be exactly the same as the primary

  database.

  Incorrect answer:

  A, B: Logical standby databases convert the redo generated at the Primary database into data and SQL and then re-apply those SQL transactions on the Logical standby, thus physical structures and organization will be different from the

  Primary database. Users can read from logical standby databases while the changes are being applied and, if the GUARD is set to STANDBY (ALTER DATABASE GUARD STANDBY;), write to tables in the Logical standby database that are

  not being maintained by SQL Apply. Unfortunately there are a number of unsupported objects (ie: tables or sequences owned by SYS, tables that use table compression, tables that underlie a materialized view or Global temporary tables

  (GTTs)) and unsupported data types (ie: Datatypes BFILE, ROWID, and UROWID, user-defined TYPEs, Multimedia data types like Oracle Spatial, ORDDICOM, and Oracle Text Collections (e.g. nested tables, VARRAYs), SecureFile LOBs,

  OBJECT RELATIONAL XMLTypes and BINARY XML).[2] Physical standby may be appropriate in such a case.

• Question 36:

  Flash in the Oracle Exadata Database Machine is of lower latency (and enables faster access to data) than:

  A. Memory
  B. Memory and locally attached disk
  C. Memory and network-attached disk
  D. Locally attached and network-attached disk
  D. Locally attached and network-attached disk

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  The Exadata Smart Flash Cache is also used to reduce the latency of log write I/O eliminating performance bottlenecks that might occur due to database logging.

  Flash memory has very good average write latency. It is faster than locally attached and network- attached disks. However, it is not faster than Memory (RAM).

• Question 37:

  What areas can SQL Access Advisor give advice on?

  A. Partitioning advice, index advice, and materialized views advice
  B. Index advice and compression advice
  C. Index advice and data masking advice
  D. Partitioning advice and compression advice
  A. Partitioning advice, index advice, and materialized views advice

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  The SQL Access Advisor was introduced in Oracle 10g to make suggestions about additional indexes and materialized views which might improve system performance. Oracle 11g has made two significant changes to the SQL Access

  Advisor:

  The advisor now includes advice on partitioning schemes that may improve performance. The original workload manipulation has been deprecated and replaced by SQL tuning sets.

• Question 38:

  How many Exadata Storage Server cells are there in a Full Rack Exadata database machine configuration that has 8 Database Server nodes?

  B. 14
  C. 16
  D. 24
  B. 14

• Question 39:

  How does compression affect resource utilization?

  A. Reduces the amount of CPU and disk utilization
  B. Increases the amount of CPU and disk utilization
  C. Reduces the amount of disk but increases CPU utilization for loading
  D. Increases the amount of disk but reduces CPU utilization for loading!
  C. Reduces the amount of disk but increases CPU utilization for loading

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  Compression is useful because it helps reduce the consumption of resources such as data space or transmission capacity. Because compressed data must be decompressed to be used, this extra processing imposes computational or other costs through decompression.

• Question 40:

  What is the estimated maximum speed of data loads for a Quarter Rack with the Exadata Storage Server?

  A. 1 TB/hr
  B. 2 TB/hr
  C. 4 TB/hr
  D. 5 TB/hr
  E. It depends on the number of CPUs in the server.
  A. 1 TB/hr