count_if
aggregate function
Applies to: Databricks SQL Databricks Runtime
Returns the number of true values for the group in expr
.
Syntax
count_if ( [ALL | DISTINCT] expr ) [ FILTER ( WHERE cond ) ]
This function can also be invoked as a window function using the OVER
clause.
Arguments
expr
: A BOOLEAN expression.cond
: An optional boolean expression filtering the rows used for aggregation.
Returns
A BIGINT
.
count_if(expr) FILTER(WHERE cond)
is equivalent to count_if(expr AND cond)
.
If DISTINCT
is specified only unique rows are counted.
Examples
> SELECT count_if(col % 2 = 0) FROM VALUES (NULL), (0), (1), (2), (2), (3) AS tab(col);
3
> SELECT count_if(DISTINCT col % 2 = 0) FROM VALUES (NULL), (0), (1), (2), (2), (3) AS tab(col);
2
> SELECT count_if(col IS NULL) FROM VALUES (NULL), (0), (1), (2), (3) AS tab(col);
1