DEA-C01 Data Operations and Support Practice Question

Correct answer & explanation

Using DISTSTYLE KEY on the join column for large tables colocates data with the same key on the same slice, reducing the need for data redistribution operations like DS_DIST_ALL_INNER and DS_BCAST_INNER. Option C is correct because increasing the number of slices by resizing the cluster distributes data across more compute nodes, allowing more parallelism and reducing the relative impact of data redistribution. Option A is incorrect because setting DISTSTYLE to ALL on both tables would broadcast each table to all nodes, increasing data movement and likely worsening performance. Option D is incorrect because SORTKEYs optimize range-restricted scans and sorting, not join data movement. Option E is incorrect because dropping and recreating tables with the same DDL does not change distribution or sort strategies, so it does not address the root cause of excessive redistribution.