Aggregate Functions

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This functionality is in beta and is subject to change. The design and code is less mature than official GA features and is being provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features.

Functions for computing a single result from a set of input values. Elasticsearch SQL supports aggregate functions only alongside grouping (implicit or explicit).

General Purpose

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AVG

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Synopsis:

AVG(numeric_field) 

Input:

numeric field

Output: double numeric value

Description:Returns the Average (arithmetic mean) of input values.

SELECT AVG(salary) AS avg FROM emp;

      avg:d
---------------
48248.55

COUNT

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Synopsis:

COUNT(expression) 

Input:

a field name, wildcard (*) or any numeric value

Output: numeric value

Description:Returns the total number (count) of input values.

In case of COUNT(*) or COUNT(<literal>), all values are considered (including null or missing ones).

In case of COUNT(<field_name>) null values are not considered.

SELECT COUNT(*) AS count FROM emp;

     count
---------------
100

COUNT(ALL)

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Synopsis:

COUNT(ALL field_name) 

Input:

a field name

Output: numeric value

Description:Returns the total number (count) of all non-null input values. COUNT(<field_name>) and COUNT(ALL <field_name>) are equivalent.

SELECT COUNT(ALL last_name) AS count_all, COUNT(DISTINCT last_name) count_distinct FROM emp;

   count_all   |  count_distinct
---------------+------------------
100            |96

COUNT(DISTINCT)

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Synopsis:

COUNT(DISTINCT field_name) 

Input:

a field name

Output: numeric value

Description:Returns the total number of distinct non-null values in input values.

SELECT COUNT(DISTINCT hire_date) unique_hires, COUNT(hire_date) AS hires FROM emp;

  unique_hires  |     hires
----------------+---------------
99              |100

MAX

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Synopsis:

MAX(field_name) 

Input:

a numeric field

Output: same type as the input

Description:Returns the maximum value across input values in the field field_name.

SELECT MAX(salary) AS max FROM emp;

      max
---------------
74999

MIN

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Synopsis:

MIN(field_name) 

Input:

a numeric field

Output: same type as the input

Description:Returns the minimum value across input values in the field field_name.

SELECT MIN(salary) AS min FROM emp;

      min
---------------
25324

SUM

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Synopsis:

SUM(field_name) 

Input:

a numeric field

Output: bigint for integer input, double for floating points

Description:Returns the sum of input values in the field field_name.

SELECT SUM(salary) AS sum FROM emp;

      sum
---------------
4824855

Statistics

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KURTOSIS

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Synopsis:

KURTOSIS(field_name) 

Input:

a numeric field

Output: double numeric value

Description:Quantify the shape of the distribution of input values in the field field_name.

SELECT MIN(salary) AS min, MAX(salary) AS max, KURTOSIS(salary) AS k FROM emp;

      min      |      max      |        k
---------------+---------------+------------------
25324          |74999          |2.0444718929142986

PERCENTILE

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Synopsis:

PERCENTILE(
    field_name,  
    numeric_exp) 

Input:

a numeric field

a numeric expression

Output: double numeric value

Description:Returns the nth percentile (represented by numeric_exp parameter) of input values in the field field_name.

SELECT languages, PERCENTILE(salary, 95) AS "95th" FROM emp
       GROUP BY languages;

   languages   |      95th
---------------+-----------------
null           |74999.0
1              |72790.5
2              |71924.70000000001
3              |73638.25
4              |72115.59999999999
5              |61071.7

PERCENTILE_RANK

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Synopsis:

PERCENTILE_RANK(
    field_name,  
    numeric_exp) 

Input:

a numeric field

a numeric expression

Output: double numeric value

Description:Returns the nth percentile rank (represented by numeric_exp parameter) of input values in the field field_name.

SELECT languages, PERCENTILE_RANK(salary, 65000) AS rank FROM emp GROUP BY languages;

   languages   |      rank
---------------+-----------------
null           |73.65766569962062
1              |73.7291625157734
2              |88.88005607010643
3              |79.43662623295829
4              |85.70446389643493
5              |100.0

SKEWNESS

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Synopsis:

SKEWNESS(field_name) 

Input:

a numeric field

Output: double numeric value

Description:Quantify the asymmetric distribution of input values in the field field_name.

SELECT MIN(salary) AS min, MAX(salary) AS max, SKEWNESS(salary) AS s FROM emp;

      min      |      max      |        s
---------------+---------------+------------------
25324          |74999          |0.2707722118423227

STDDEV_POP

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Synopsis:

STDDEV_POP(field_name) 

Input:

a numeric field

Output: double numeric value

Description:Returns the population standard deviation of input values in the field field_name.

SELECT MIN(salary) AS min, MAX(salary) AS max, STDDEV_POP(salary) AS stddev
       FROM emp;

      min      |      max      |      stddev
---------------+---------------+------------------
25324          |74999          |13765.125502787832

SUM_OF_SQUARES

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Synopsis:

SUM_OF_SQUARES(field_name) 

Input:

a numeric field

Output: double numeric value

Description:Returns the sum of squares of input values in the field field_name.

SELECT MIN(salary) AS min, MAX(salary) AS max, SUM_OF_SQUARES(salary) AS sumsq
       FROM emp;

      min      |      max      |     sumsq
---------------+---------------+----------------
25324          |74999          |2.51740125721E11

VAR_POP

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Synopsis:

VAR_POP(field_name) 

Input:

a numeric field

Output: double numeric value

Description:Returns the population variance of input values in the field field_name.

SELECT MIN(salary) AS min, MAX(salary) AS max, VAR_POP(salary) AS varpop FROM emp;

      min      |      max      |     varpop
---------------+---------------+----------------
25324          |74999          |1.894786801075E8