Microsoft 70-762 Online Practice Questions and Exam Preparation

Microsoft 70-762 Online Questions & Answers

• Question 111:

  Note: This question is part of a series of questions that use the same or similar answer choices. An Answer choice may be correct for more than one question in the series. Each question independent of the other questions in this series.

  Information and details provided in a question apply only to that question.

  You are a database developer for a company. The company has a server that has multiple physical disks. The disks are not part of a RAID array. The server hosts three SQL Server instances. There are many SQL jobs that run during off-

  peak hours.

  You must monitor the SQL Server instances in real time and optimize the server to maximize throughput, response time, and overall SQL performance.

  You need to collect query performance data while minimizing the performance impact on the SQL Server.

  What should you do?

  A. A. Create a sys.dm_os_waiting_tasks query.
  B. Create a sys.dm_exec_sessions query.
  C. Create a Performance Monitor Data Collector Set.
  D. Create a sys.dm_os_memory_objects query.
  E. Create a sp_configure `max server memory' query.
  F. Create a SQL Profiler trace.
  G. Create a sys.dm_os_wait_stats query.
  H. Create an Extended Event.
  C. Create a Performance Monitor Data Collector Set.

  ---

  SQL Server Data Collector is a feature for performance monitoring and tuning available in SQL Server Management Studio.

  Integration Services packages transform and load the collected data into the Microsoft Data Warehouse database.

  Collection sets are defined and deployed on a server instance and can be run independently of each other. Each collection set can be applied to a target that matches the target types of all the collector types that are part of a collection set.

  The collection set is run by a SQL Server Agent job or jobs, and data is uploaded to the management data warehouse on a predefined schedule.

  Predefined data collection sets include:

  The Query Statistics data collection set collects information about query statistics, activity, execution plans and text on the SQL Server instance. It does not store all executed statements, only 10 worst performing ones.

  Disk Usage data collection set collects information about disk space used by both data and log files for all databases on the SQL Server instance, growth trends, and average day growth.

  Etc.

  References:

  http://www.sqlshack.com/sql-server-performance-monitoring-data-collector/

• Question 112:

  You have several real-time applications that constantly update data in a database. The applications run more than 400 transactions per second that insert and update new metrics from sensors.

  A new web dashboard is released to present the data from the sensors. Engineers report that the applications take longer than expected to commit updates.

  You need to change the dashboard queries to improve concurrency and to support reading uncommitted data.

  What should you do?

  A. Use the NOLOCK option.
  B. Execute the DBCC UPDATEUSAGE statement.
  C. Use the max worker threads option.
  D. Use a table-valued parameter.
  E. Set SET ALLOW_SNAPSHOT_ISOLATION to ON.
  F. Set SET XACT_ABORT to ON.
  G. Execute the ALTER TABLE T1 SET (LOCK_ESCALATION = AUTO); statement.
  H. Use the OUTPUT parameters.
  A. Use the NOLOCK option.

  ---

  The NOLOCK hint allows SQL to read data from tables by ignoring any locks and therefore not being blocked by other processes. This can improve query performance, but also introduces the possibility of dirty reads.

  Incorrect Answers:

  F: When SET XACT_ABORT is ON, if a Transact-SQL statement raises a run-time error, the entire transaction is terminated and rolled back.

  G: DISABLE, not AUTO, would be better.

  There are two more lock escalation modes: AUTO and DISABLE.

  The AUTO mode enables lock escalation for partitioned tables only for the locked partition. For non-partitioned tables it works like TABLE. The DISABLE mode removes the lock escalation capability for the table and that is important when

  concurrency issues are more important than memory needs for specific tables.

  Note: SQL Server's locking mechanism uses memory resources to maintain locks. In situations where the number of row or page locks increases to a level that decreases the server's memory resources to a minimal level, SQL Server's locking strategy converts these locks to entire table locks, thus freeing memory held by the many single row or page locks to one table lock. This process is called lock escalation, which frees memory, but reduces table concurrency.

  References: https://www.mssqltips.com/sqlservertip/2470/understanding-the-sql-server-nolock-hint/

• Question 113:

  Note: This question is part of a series of questions that present the same scenario. Each question in the series contains a unique solution. Determine whether the solution meets the stated goals.

  You have a database that contains a table named Employees. The table stores information about the employees of your company.

  You need to implement and enforce the following business rules:

  Limit the values that are accepted by the Salary column.

  Prevent salaries less than $15,000 and greater than $300,000 from being entered.

  Determine valid values by using logical expressions.

  Do not validate data integrity when running DELETE statements.

  Solution: You implement a check constraint on the table.

  Does the solution meet the goal?

  A. Yes
  B. No
  A. Yes

  ---

  References: https://en.wikipedia.org/wiki/Check_constraint

• Question 114:

  Note: This question is part of a series of questions that use the same scenario. For your convenience, the scenario is repeated in each question. Each question presents a different goal and answer choices, but the text of the scenario is

  exactly the same in each question in this series.

  You have a database that contains the following tables: BlogCategory, BlogEntry, ProductReview, Product, and SalesPerson. The tables were created using the following Transact SQL statements:

  

  You must modify the ProductReview Table to meet the following requirements:

  1. The table must reference the ProductID column in the Product table

  2. Existing records in the ProductReview table must not be validated with the Product table.

  3. Deleting records in the Product table must not be allowed if records are referenced by the ProductReview table.

  4. Changes to records in the Product table must propagate to the ProductReview table.

  You also have the following database tables: Order, ProductTypes, and SalesHistory, The transact-SQL statements for these tables are not available. You must modify the Orders table to meet the following requirements:

  1. Create new rows in the table without granting INSERT permissions to the table.

  2. Notify the sales person who places an order whether or not the order was completed.

  You must add the following constraints to the SalesHistory table:

  - a constraint on the SaleID column that allows the field to be used as a record identifier

  - a constant that uses the ProductID column to reference the Product column of the ProductTypes table

  - a constraint on the CategoryID column that allows one row with a null value in the column

  - a constraint that limits the SalePrice column to values greater than four

  Finance department users must be able to retrieve data from the SalesHistory table for sales persons where the value of the SalesYTD column is above a certain threshold. You plan to create a memory-optimized table named SalesOrder. The table must meet the following requirements:

  - The table must hold 10 million unique sales orders.

  - The table must use checkpoints to minimize I/O operations and must not use transaction logging.

  -Data loss is acceptable.

  Performance for queries against the SalesOrder table that use Where clauses with exact equality operations must be optimized.

  You need to create the Sales Order table

  How should you complete the table definition? To answer? select the appropriate Transact-SQL segments in the answer area.

  Hot Area:

  

  

  ---

  Box 1: NONCLUSTERED HASHWITH (BUCKET_COUNT = 10000000)

  Hash index is preferable over a nonclustered index when queries test the indexed columns by use of a WHERE clause with an exact equality on all index key columns. We should use a bucket count of 10 million.

  Box 2: SCHEMA_ONLY

  Durability: The value of SCHEMA_AND_DATA indicates that the table is durable, meaning that changes are persisted on disk and survive restart or failover. SCHEMA_AND_DATA is the default value.

  The value of SCHEMA_ONLY indicates that the table is non-durable. The table schema is persisted but any data updates are not persisted upon a restart or failover of the database.

  DURABILITY=SCHEMA_ONLY is only allowed with MEMORY_OPTIMIZED=ON.

  References:https://msdn.microsoft.com/en-us/library/mt670614.aspx

• Question 115:

  Note: This question is part of a series of questions that present the same scenario. Each question in the series contains a unique solution that might meet the stated goals. Some questions sets might have more than onecorrect solution, while others might not have a correct solution.

  After you answer a question in this section, you will NOT be able to return to it. As a result, these questions will not appear in the review screen.

  You need to collect data from the following two sources:

  1.

  The performance counters of the operating system

  2.

  Microsoft SQL Server events

  You must analyze the two datasets side-by side by using a single tool.

  Solution: You use SQL Server Profiler and SQL Server Extended Events to collect performance data. You use SQL Server Profiler to analyze the data.

  Does this meet the goal?

  A. Yes
  B. No
  B. No

  ---

  Reference: https://www.sqlshack.com/dba-guide-sql-server-performance-troubleshooting-part-2-monitoring-utilities/

• Question 116:

  DRAG DROP

  You are a database developer for a company that delivers produce and other refrigerated goods to grocery stores. You capture the food storage temperature for delivery vehicles by using Internet of Things (loT) devices. You store the

  temperature data in a database table named vchicleTewperatures. The chillerSensorNumber column stores the identifier for the loT devices.

  You need to create an indexed view that meets the following requirements:

  Persists the data on disk to reduce the amount of I/O.

  Provides the number of chillerSensorNumber items.

  Creates only a set sof summary rows.

  Select and Place:

  

  

  ---

  

• Question 117:

  Note: This question is part of a series of questions that present the same scenario. Each question in the series contains a unique solution that might meet the stated goals. Some questions sets might have more than onecorrect solution, while others might not have a correct solution.

  After you answer a question in this section, you will NOT be able to return to it. As a result, these questions will not appear in the review screen.

  You need to collect data from the following two sources:

  1.

  The performance counters of the operating system

  2.

  Microsoft SQL Server events

  You must analyze the two datasets side-by side by using a single tool.

  Solution: You use dynamic management views and SQL Server Profiler to collect performance data. You use SQL Server Management Studio (SSMS) to analyze the data.

  Does this meet the goal?

  A. Yes
  B. No
  A. Yes

  ---

  Reference: https://www.sqlshack.com/dba-guide-sql-server-performance-troubleshooting-part-2-monitoring-utilities/

• Question 118:

  Background

  You have a database named HR1 that includes a table named Employee.

  You have several read-only, historical reports that contain regularly changing totals. The reports use multiple queries to estimate payroll expenses. The queries run concurrently.

  Users report that the payroll estimate reports do not always run. You must monitor the database to identify issues that prevent the reports from running.

  You plan to deploy the application to a database server that supports other applications.

  You must minimize the amount of storage that the database requires.

  Employee Table

  You use the following Transact-SQL statements to create, configure, and populate the Employee table:

  

  Application

  You have an application that updates the Employees table. The application calls the following stored procedures simultaneously and asynchronously:

  The application uses views to control access to data. Views must meet the following requirements:

  

  Users must only be able to modify data in the Employee table by using the vwEmployee view. You must prevent users from viewing the view definition in catalog views.

  You need to identify the view attribute to use when creating vwEmployee.

  In the table below, identify the attributes that you must use.

  NOTE: Make only one selection in each column.

  Hot Area:

  

  

  ---

  References:

  https://msdn.microsoft.com/en-us/library/ms187956.aspx

• Question 119:

  Note: This question is part of a series of questions that use the same scenario. For your convenience, the scenario is repeated in each question. Each question presents a different goal and answer choices, but the text of the scenario is exactly the same in each question in this series.

  You have a database that contains the following tables: BlogCategory, BlogEntry, ProductReview, Product, and SalesPerson. The tables were created using the following Transact SQL statements:

  

  You must modify the ProductReview Table to meet the following requirements:

  1. The table must reference the ProductID column in the Product table

  2. Existing records in the ProductReview table must not be validated with the Product table.

  3. Deleting records in the Product table must not be allowed if records are referenced by the ProductReview table.

  4. Changes to records in the Product table must propagate to the ProductReview table.

  You also have the following database tables: Order, ProductTypes, and SalesHistory. The transact-SQL statements for these tables are not available.

  You must modify the Orders table to meet the following requirements:

  1. Create new rows in the table without granting INSERT permissions to the table.

  2. Notify the sales person who places an order whether or not the order was completed.

  You must add the following constraints to the SalesHistory table:

  - a constraint on the SaleID column that allows the field to be used as a record identifier - a constant that uses the ProductID column to reference the Product column of the ProductTypes table

  - a constraint on the CategoryID column that allows one row with a null value in the column

  - a constraint that limits the SalePrice column to values greater than four

  Finance department users must be able to retrieve data from the SalesHistory table for sales persons where the value of the SalesYTD column is above a certain threshold.

  You plan to create a memory-optimized table named SalesOrder. The table must meet the following requirements:

  - The table must hold 10 million unique sales orders.

  - The table must use checkpoints to minimize I/O operations and must not use transaction logging.

  -Data loss is acceptable.

  Performance for queries against the SalesOrder table that use Where clauses with exact equality operations must be optimized.

  You need to create a stored procedure named spDeleteCategory to delete records in the database. The stored procedure must meet the following requirements:

  1. Delete records in both the BlogEntry and BlogCategory tables where CategoryId equals parameter @CategoryId.

  2. Avoid locking the entire table when deleting records from the BlogCategory table.

  3. If an error occurs during a delete operation on either table, all changes must be rolled back, otherwise all changes should be committed.

  How should you complete the procedure? To answer, select the appropriate Transact-SQL segments in the answer area.

  Hot Area:

  

  

  ---

  Box 1: SET TRANSACTION ISOLATION LEVEL READ COMMITTED

  You can minimize locking contention while protecting transactions from dirty reads of uncommitted data modifications by using either of the following:

  * The READ COMMITTED isolation level with the READ_COMMITTED_SNAPSHOT database option set ON.

  * The SNAPSHOT isolation level. With ROWLOCK we should use READ COMMITTED

  Box 2: ROWLOCK Requirement: Avoid locking the entire table whendeleting records from the BlogCategory table ROWLOCK specifies that row locks are taken when page or table locks are ordinarily taken. When specified in transactions operating at the SNAPSHOT isolation level, row locks are not taken unless ROWLOCK is combined with other table hints that require locks, such as UPDLOCK and HOLDLOCK. Incorrect: Not TABLOCKX TABLOCKX specifies that an exclusive lock is taken on the table.

  Box 3: COMMIT Box 4: ROLLBACK

  References:

  https://msdn.microsoft.com/en-us/library/ms187373.aspx

  https://msdn.microsoft.com/en-us/library/ms187967.aspx

• Question 120:

  Note: This question is part of a series of questions that use the same or similar answer choices. An Answer choice may be correct for more than one question in the series. Each question independent of the other questions in this series.

  Information and details provided in a question apply only to that question.

  You are a database developer for a company. The company has a server that has multiple physical disks. The disks are not part of a RAID array. The server hosts three Microsoft SQL Server instances. There are many SQL jobs that run

  during off-peak hours.

  You must monitor the SQL Server instances in real time and optimize the server to maximize throughput, response time, and overall SQL performance.

  You need to ensure that the performance of each instance is consistent for the same queried and query plans.

  What should you do?

  A. A. Create a sys.dm_os_waiting_tasks query.
  B. Create a sys.dm_exec_sessions query.
  C. Create a Performance Monitor Data Collector Set.
  D. Create a sys.dm_os_memory_objects query.
  E. Create a sp_configure `max server memory' query.
  F. Create a SQL Profiler trace.
  G. Create asys.dm_os_wait_stats query.
  H. Create an Extended Event.
  H. Create an Extended Event.

  ---

  Advanced Viewing of Target Data from Extended Events in SQL Server

  When your event session is currently active, you might want to watch the event data in real time, as it is received by the target.

  Management > Extended Events > Sessions > [your-session] > Watch Live Data.

  The query_post_execution_showplan extended event enables you to see the actual query plan in the SQL Server Management Studio (SSMS) UI. When the Details pane is visible, you can see a graph of the query plan on the Query Plan

  tab.

  By hovering over a node on the query plan, you cansee a list of property names and their values for the node.

  

  References: https://msdn.microsoft.com/en-us/library/mt752502.aspx