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Apache Pig COUNT Function

The Apache Pig COUNT function is used to count the number of elements in a bag. It requires a preceding GROUP ALL statement for global counts and a GROUP BY statement for group counts. It ignores the null values.

Example of COUNT Function

In this example, we count the tuples in the bag.

Steps to execute COUNT Function

• Create a text file in your local machine and insert the list of tuples.

• Check the tuples inserted in the text files.

• Upload the text files on HDFS in the specific directory.

• Open the pig MapReduce run mode.

• Load the file that contains the data.

• Now, execute and verify the data.

• Let’s group the data on the basis of ‘a1’ field.

• Let’s return the count of given tuples.

Here, we got the desired output.