Microsoft DP-800 Exam Dumps

GitHub documents that repository custom instructions for Copilot Chat can be disabled for your own use in the editor settings, and that doing so does not affect other users. In VS Code, this is controlled through settings related to instruction files, where you can disable the use of repository instruction files for your own environment.

The other options are incorrect:

B is not a documented mechanism for disabling repository-level Copilot instructions.

C would remove the repository instruction file itself and therefore affect everyone using that repository, which violates the requirement.

This also does not meet the goal. DROP PARTITION SCHEME removes the partition scheme object from the database; it is not the command used to remove just the rows for the oldest month from a partitioned table. Microsoft's DROP PARTITION SCHEME documentation is explicit that the statement removes the partition scheme itself.

For removing only the oldest month's rows with minimal impact, Microsoft points to partition-level maintenance operations such as truncating a single partition on a partitioned table. That targets only the needed data subset and is more efficient for retention workloads.

The best explanation is an open explicit transaction. During the incident, session 72 was sleeping but still had open_transaction_count = 1, and sys.dm_exec_input_buffer(72, NULL) showed only BEGIN TRANSACTION UPDATE Sales.Orders. That pattern indicates the session executed an update inside an explicit transaction and then remained idle without committing or rolling back, while still holding locks. Other sessions showing blocking_session_id = 72 is the expected symptom of that situation. Microsoft explains that blocking occurs when one session holds a lock on a resource and another session requests a conflicting lock, and sleeping sessions can continue to block if they retain locks through an open transaction.

This also fits the observed behavior that the timeouts stopped only after session 72 was terminated. Killing the session would roll back the active transaction and release the locks, allowing waiting updates to continue. That is much more consistent with an uncommitted transaction than with a deadlock, because deadlocks are normally detected and one session is chosen as the victim automatically rather than persisting until manual termination.

Yes, this meets the goal. Microsoft documents that on a partitioned table, you can use TRUNCATE TABLE ... WITH (PARTITIONS (...)) to remove data from a specific partition, and that this is an efficient maintenance operation that targets only that data subset rather than the whole table. Microsoft's partitioning guidance explicitly lists truncating a single partition as an example of a fast partition-level maintenance or retention operation.

That matches the requirement to remove the oldest month while minimizing impact on other queries. Because the table is already partitioned by month on OrderDate, identifying the partition number for that oldest month and truncating only that partition is the correct low-impact approach, assuming the table and indexes are aligned as required for partition truncation.

The table definition allows Owner to be nullable because it was created as Owner nvarchar(100) without NOT NULL. Since the question asks what to add so that future rows must have a value, a check constraint such as CHECK (Owner IS NOT NULL) is the appropriate choice. Microsoft documents that check constraints validate future INSERT and UPDATE operations against the constraint condition.

The other options do not solve the requirement:

A foreign key enforces referential integrity, not non-null entry by itself.

A nonclustered index does not require values to be present.

A unique constraint prevents duplicate values but still does not serve as the right mechanism here for enforcing presence across future writes. Microsoft's constraint documentation also notes that primary-key columns are implicitly NOT NULL, which helps distinguish nullability enforcement from other constraint types.