Multiple choice technology databases

Which column is more skewed? Total no. of rows in the table are 1000

  1. Deptno column has 5 distinct values, each having 200 rows

  2. Grade column has 2 distinct values having 1 and 999 rows

  3. Location column has 3 distinct values having 300, 400 and 300 rows

  4. All columns have same skewness
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Skewness measures data distribution unevenness. Grade column with 1 and 999 rows is extremely skewed - 99.9% of rows have one value. Deptno (200 each) and Location (300,400,300) have much more even distributions. Higher skewness means more uneven distribution, which affects query optimization and statistics collection.

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