tajo-docs/src/main/sphinx/functions/agg_func.rst

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Aggregation Functions
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.. function:: avg (expression)

  Returns the average of all input values.

  :param expression:
  :type expression: int | float
  :rtype: float8

.. function:: corr (expression1, expression2)

  Returns the coefficient of correlation between a set of number pairs.

  :param expression1:
  :param expression2:
  :type expression1: int | float
  :type expression2: int | float
  :rtype: float8

.. function:: count()

  Returns the number of input rows.

  :rtype: int8

.. function:: last_value(expression)

  Returns the last value of expression.

  :param expression:
  :type expression: int | float | date | time | timestamp | text
  :rtype: same as parameter data type

.. function:: max(expression)

  Returns the maximum value of expression.

  :param expression:
  :type expression: int | float | date | time | timestamp | text
  :rtype: same as parameter data type

.. function:: min(expression)

  Returns the minimum value of expression.

  :param expression:
  :type expression: int | float | date | time | timestamp | text
  :rtype: same as parameter data type

.. function:: stddev_pop(expression)

  Returns the population standard deviation of a set of numbers.

  :param expression:
  :type expression: int | float
  :rtype: float8

.. function:: stddev_samp(expression)

  Returns the sample standard deviation of a set of numbers.

  :param expression:
  :type expression: int | float
  :rtype: float8

.. function:: sum(expression)

  Returns the sum of a set of numbers.

  :param expression:
  :type expression: int | float
  :rtype: same as parameter data type

.. function:: var_pop(expression)

  Returns the variance of a set of numbers.

  :param expression:
  :type expression: int | float
  :rtype: float8

.. function:: var_samp(expression)

  Returns the unbiased sample variance of a set of numbers.

  :param expression:
  :type expression: int | float
  :rtype: float8