The database commonly uses an index range scan to access selective data. The selectivity is the percentage of rows in the table that the query selects, with 0 meaning no rows and 1 meaning all rows. Selectivity is tied to a query predicate, such as WHERE last_name LIKE 'A%', or a combination of predicates.
Types of Distribution: Intensive, Selective and Exclusive Distribution. Some of the important types of distribution in international market are 1. Intensive 2. Selective and 3. Exclusive distribution.
The following are universal properties that are common to all normal distributions. 1  The shape and position of a normal distribution depends on the population mean (mu) and the population standard deviation (sigma). 2  A normal distribution is symmetric, and the mean = median = mode.ne of the most important classes of continuous distributions is the normal distribution. Since its discovery more than 350 years ago, it has developed into an indispensable tool for every branch of science, industry, and commerce.