How to eliminate null values when grouping data in DB2?

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There are a few ways to eliminate null values when grouping data in DB2:

1. Use the COALESCE function to replace null values with a default value:

SELECT COALESCE(column_name, 'default_value') AS new_column_name, COUNT(*) 
FROM table_name 
GROUP BY new_column_name;

1. Use the WHERE clause to exclude null values:

SELECT column_name, COUNT(*) 
FROM table_name 
WHERE column_name IS NOT NULL 
GROUP BY column_name;

1. Filter out null values using the HAVING clause:

SELECT column_name, COUNT(*) 
FROM table_name 
GROUP BY column_name 
HAVING column_name IS NOT NULL;