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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 next of the scenario is exactly the same in each question in this series

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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 next of the scenario is exactly the same in each question in this series.

Start of repeated scenario

Contoso, Ltd. has Microsoft SQL Server databases that support a custom application. The current SQL Server environment consists of two servers: ContosoSQL1 and ContosoSQL2. These two servers participate in an Always On Availability Group named ContosoAG1 that is configured to use synchronous-commit with automatic failover. The secondary replica is not configured for read-only access.

The application performs both transactional processing and historical data retrieval in a database named ContosoDB. The application includes an inventory management module. The inventory management module and database have experienced performance issues.

Users report that a query named InventoryQuery1 takes a long time to complete. The query is shown as follows:

SELECT ProductNumber, Name, ProductLine

FROM Production.Product

WHERE ProductNumber = N'<specific product>’

The query plan used by SQL Server for this query is shown in the exhibit. (Click the Exhibit tab.) Various performance issues, including frequent long-term blocking episodes, prevent business users from completing their daily tasks. You suspect the tempdb database resources could be responsible. You must create Blocking reports for the ContosoDB database to identify issues.

Exhibit.

You plan to use Extended Events to review all Transact-SQL statements that are run against the ContosoSQL1 instance. The output from the Extended Events session must contain both start and stop events and must be written to a file. You must configure the Extended Events session to minimize possible data loss and reduce the effect on server performance.

You plan to deploy an additional secondary replica named ContosoSQL3 to ContosoAG1. Read-only traffic must be load-balanced between the two secondary replicas, regardless of which instance is the primary replica. Contoso plans to add an additional dedicated reporting system that will rely on real-time data from the transactional databases.

End of repeated scenario

You need to troubleshoot and resolve the issue with InventoryQuery1.

Use the drop-down menus to select the answer choice that answers each question based on the information presented in the graphic.

Answer:

Explanation:

Box 1: Key Lookup (clustered) They Key Lookup (clustered) should be less than 50%.

Box 2: Change the table’s primary key to the Product.ProductNumber column.

Incorrect: Non-Clustered Index Seek Non-Clustered Index Seek occurs when Columns part of non-clustered index accessed in query and rows located in the B+ tree. It is good and ideal to have a Non-Clustered Index Seek. Action: Evaluate other operators

References: https://www.sqlshack.com/sql-server-query-execution-plans-beginners-non-clustered-index­operators/

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