Ex: SELECT COUNT(*) FROM customers ... aggregate_function can be one of the built-in functions in SQL, such as SUM, AVG, MIN, MAX, COUNT, or DISTINCT. The column_name is the name of the column ...

This function returns the approximate number of unique non-null values in a group. :::image type="icon" source="../../includes/media/topic-link-icon.svg" border ...

SELECT options refine results As we saw in the last article, the SQL SELECT ... We’ll look at the DISTINCT keyword, which triggers some useful optional functionality. Functions are built-in ...