T-SQL Command for Disk Space Usage and Data Skew in SQL Data Warehouse

Correct Answer: A.

The correct answer to the question is A. DBCC PDW_SHOWSPACEUSED.

DBCC (Database Console Command) is a T-SQL command used to perform database consistency checks, view database metadata and perform maintenance operations. In SQL Data Warehouse, DBCC commands have been extended to include commands specific to SQL Data Warehouse.

DBCC PDW_SHOWSPACEUSED is a SQL Data Warehouse specific command that is used to show the disk space usage and data skew of tables within a database. This command provides useful information to data engineers and database administrators to help them optimize their database and storage.

The output of the command includes the following information:

• The name of the table
• The number of rows in the table
• The reserved space for the table (in KB)
• The amount of space used by the table (in KB)
• The amount of unused space for the table (in KB)
• The percentage of space used by the table
• The distribution of rows across distributions (data skew)

DBCC PDW_SHOWPARTITIONSTATS is another DBCC command that is used to display information about the partitions of a table, such as the number of rows, reserved space, and used space for each partition. This command is useful for analyzing the distribution of data within a partitioned table.

DBCC PDW_SHOWEXECUTIONPLAN is a command used to display the execution plan for a query. This command is useful for analyzing the performance of a query and identifying areas for optimization.

In summary, the DBCC PDW_SHOWSPACEUSED command is useful for checking the disk space usage and data skew of tables in SQL Data Warehouse, making it the correct answer to the question.