MODE SQL Notes
Comparison operators LIKE is case sensitive ILIKE is not BETWEEN includes the range bounds IS NULL is for missing values. column=NULL will not work. For non null values - use IS NOT NULL. Don’t use NOT IS NULL Aggregate function COUNT COUNT(col) gives of count of col where values are not null. This is the main difference between COUNT(*) and COUNT(col) SUM, AVG and COUNT can only be used for numeric values. (duh!) AVG ignores null values completely. Does not take in the denominator MIN and MAX can be used for numeric, date, chars GROUP BY ...