Here is how to change column from NULL to NOT NULL in SQL Server, MySQL, PostgreSQL using ALTER TABLE statement.
Redshift
How to Calculate Running Total in Redshift
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Cumulative Total allows you to track running totals over time. Here’s how to calculate running total in Redshift.
How to Calculate Moving Average in Redshift
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Rolling Average helps smoothen numerical trends in data. Here’s how to calculate moving average in Redshift using SQL query.