Window

Function Name	Description
COUNT	Returns the total number of records for the specified expression.
COVAR_POP	Returns the population covariance for non-NULL pairs across all input values.
COVAR_SAMP	Returns the sample covariance for non-NULL pairs across all input values.
CUME_DIST	Returns the cumulative distribution of the current row with regard to other values within the same window partition.
DENSE_RANK	Returns the rank of the current row within its partition and ordering. Rows that are equal will have the same rank.
FIRST_VALUE	Returns the first value within an ordered group of a result set.
HLL	Uses HyperLogLog to return an approximation of the distinct cardinality of the input.
LAG	Returns the row before the current one in a partition based on the `ORDER BY` clause without the need for a self-join. If there are no rows, this function returns `NULL`.
LEAD	Returns the row after the current one in the same result set without the need for a self-join. If there are no rows, this function returns `NULL`.
MAX	Returns the maximum value among the non-NULL input expressions.
MIN	Returns the minimum value among the non-NULL input expressions.
NDV	Returns an approximate distinct value number, similar to `COUNT(DISTINCT col)`. NDV can return results faster than using the combination of COUNT and DISTINCT while using a constant amount of memory, resulting in less memory usage for columns with high cardinality.
NTILE	Equally splits the rows in each partition into ranked parts specified by the integer value and starting from 1. This function requires the `ORDER BY` clause.
PERCENT_RANK	Returns the relative rank of the current row in the partition based on the `ORDER BY` clause. The displayed percentage ranges from 0.0 to 1.0.
RANK	Returns the rank of the current row within its partition and placement order. Rows that are equal have the same rank. However, the count of tied rows is added to the next rank, instead of being incremented by one. The rank value starts at 1 and increases sequentially.
ROW_NUMBER	Returns the row number for the current row based on the `ORDER BY` clause within each partition. Rows containing identical values receive different row numbers.
SUM	Returns the sum of non-NULL input expressions.
VAR_POP	Returns the population variance of non-NULL records.
VAR_SAMP	Returns the sample variance of non-NULL records.