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Aggregation function types at a glance

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An aggregation function performs a calculation on a set of values, and returns a single value. This article lists all available aggregation functions grouped by type. For scalar functions, see Scalar function types.

Binary functions

Function Name Description
binary_all_and() Returns aggregated value using the binary AND of the group.
binary_all_or() Returns aggregated value using the binary OR of the group.
binary_all_xor() Returns aggregated value using the binary XOR of the group.

Dynamic functions

Function Name Description
buildschema() Returns the minimal schema that admits all values of the dynamic input.
make_bag(), make_bag_if() Returns a property bag of dynamic values within the group without/with a predicate.
make_list(), make_list_if() Returns a list of all the values within the group without/with a predicate.
make_list_with_nulls() Returns a list of all the values within the group, including null values.
make_set(), make_set_if() Returns a set of distinct values within the group without/with a predicate.

Row selector functions

Function Name Description
arg_max() Returns one or more expressions when the argument is maximized.
arg_min() Returns one or more expressions when the argument is minimized.
take_any(), take_anyif() Returns a random non-empty value for the group without/with a predicate.

Statistical functions

Function Name Description
avg() Returns an average value across the group.
avgif() Returns an average value across the group (with predicate).
count(), countif() Returns a count of the group without/with a predicate.
dcount(), dcountif() Returns an approximate distinct count of the group elements without/with a predicate.
hll() Returns the HyperLogLog (HLL) results of the group elements, an intermediate value of the dcount approximation.
hll_merge() Returns a value for merged HLL results.
max(), maxif() Returns the maximum value across the group without/with a predicate.
merge_tdigest() Returns the merged tdigest value across the group, is an alias of tdigest_merge.
min(), minif() Returns the minimum value across the group without/with a predicate.
percentile() Returns a percentile estimation of the group.
percentiles() Returns percentile estimations of the group.
percentiles_array() Returns the percentile approximates of the array.
percentilesw() Returns the weighted percentile approximate of the group.
percentilesw_array() Returns the weighted percentile approximate of the array.
stdev(), stdevif() Returns the standard deviation across the group for a population that is considered a sample without/with a predicate.
stdevp() Returns the standard deviation across the group for a population that is considered representative.
sum(), sumif() Returns the sum of the elements within the group without/with a predicate.
tdigest() Returns an intermediate result for the percentiles approximation, the weighted percentile approximate of the group.
tdigest_merge() Returns the merged tdigest value across the group.
variance(), varianceif() Returns the variance across the group without/with a predicate.
variancep() Returns the variance across the group for a population that is considered representative.