COUNT
Description
This function counts the rows of a column per group. It can be applied on columns of any data type.
Use the COUNT DISTINCT function to count only the unique values in a group.
Syntax
COUNT ( table.column )
NULL handling
NULL values are not counted. If all the values in a group are NULL, the result for this group is 0.
Examples
[1] Count elements of the column. | |||||||||||
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[2] Count the number of values grouped by country. | ||||||||||||||||||||||||||
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[3] Count the number of values mixed with nulls, grouped by country. | ||||||||||||||||||
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