Doubt in word count query

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What is meant by count(1) n the below code snippet:

select word,count(1) as count from
(SELECT explode(split(sentence, " ")) AS word FROM texttable)tempTable
group by word
Feb 18 in Big Data Hadoop by Sanam
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1 answer to this question.

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The COUNT function returns the number of rows for which the expression evaluates to a non-null value. 

Since the expression "1" evaluates to non-null for every row, and since you are not removing duplicates, COUNT(1) should always return the same number as COUNT(*).

answered Feb 18 by Omkar
• 67,380 points

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