Fixed #10929 -- Added default argument to aggregates.

Thanks to Simon Charette and Adam Johnson for the reviews.
This commit is contained in:
Nick Pope 2021-02-21 01:38:55 +00:00 committed by Mariusz Felisiak
parent 59942a66ce
commit 501a8db465
11 changed files with 393 additions and 64 deletions

View file

@ -19,8 +19,8 @@ module. They are described in more detail in the `PostgreSQL docs
.. admonition:: Common aggregate options
All aggregates have the :ref:`filter <aggregate-filter>` keyword
argument.
All aggregates have the :ref:`filter <aggregate-filter>` keyword argument
and most also have the :ref:`default <aggregate-default>` keyword argument.
General-purpose aggregation functions
=====================================
@ -28,9 +28,10 @@ General-purpose aggregation functions
``ArrayAgg``
------------
.. class:: ArrayAgg(expression, distinct=False, filter=None, ordering=(), **extra)
.. class:: ArrayAgg(expression, distinct=False, filter=None, default=None, ordering=(), **extra)
Returns a list of values, including nulls, concatenated into an array.
Returns a list of values, including nulls, concatenated into an array, or
``default`` if there are no values.
.. attribute:: distinct
@ -54,26 +55,26 @@ General-purpose aggregation functions
``BitAnd``
----------
.. class:: BitAnd(expression, filter=None, **extra)
.. class:: BitAnd(expression, filter=None, default=None, **extra)
Returns an ``int`` of the bitwise ``AND`` of all non-null input values, or
``None`` if all values are null.
``default`` if all values are null.
``BitOr``
---------
.. class:: BitOr(expression, filter=None, **extra)
.. class:: BitOr(expression, filter=None, default=None, **extra)
Returns an ``int`` of the bitwise ``OR`` of all non-null input values, or
``None`` if all values are null.
``default`` if all values are null.
``BoolAnd``
-----------
.. class:: BoolAnd(expression, filter=None, **extra)
.. class:: BoolAnd(expression, filter=None, default=None, **extra)
Returns ``True``, if all input values are true, ``None`` if all values are
null or if there are no values, otherwise ``False`` .
Returns ``True``, if all input values are true, ``default`` if all values
are null or if there are no values, otherwise ``False``.
Usage example::
@ -92,9 +93,9 @@ General-purpose aggregation functions
``BoolOr``
----------
.. class:: BoolOr(expression, filter=None, **extra)
.. class:: BoolOr(expression, filter=None, default=None, **extra)
Returns ``True`` if at least one input value is true, ``None`` if all
Returns ``True`` if at least one input value is true, ``default`` if all
values are null or if there are no values, otherwise ``False``.
Usage example::
@ -114,9 +115,10 @@ General-purpose aggregation functions
``JSONBAgg``
------------
.. class:: JSONBAgg(expressions, distinct=False, filter=None, ordering=(), **extra)
.. class:: JSONBAgg(expressions, distinct=False, filter=None, default=None, ordering=(), **extra)
Returns the input values as a ``JSON`` array.
Returns the input values as a ``JSON`` array, or ``default`` if there are
no values.
.. attribute:: distinct
@ -139,10 +141,10 @@ General-purpose aggregation functions
``StringAgg``
-------------
.. class:: StringAgg(expression, delimiter, distinct=False, filter=None, ordering=())
.. class:: StringAgg(expression, delimiter, distinct=False, filter=None, default=None, ordering=())
Returns the input values concatenated into a string, separated by
the ``delimiter`` string.
the ``delimiter`` string, or ``default`` if there are no values.
.. attribute:: delimiter
@ -174,17 +176,17 @@ field or an expression returning a numeric data. Both are required.
``Corr``
--------
.. class:: Corr(y, x, filter=None)
.. class:: Corr(y, x, filter=None, default=None)
Returns the correlation coefficient as a ``float``, or ``None`` if there
Returns the correlation coefficient as a ``float``, or ``default`` if there
aren't any matching rows.
``CovarPop``
------------
.. class:: CovarPop(y, x, sample=False, filter=None)
.. class:: CovarPop(y, x, sample=False, filter=None, default=None)
Returns the population covariance as a ``float``, or ``None`` if there
Returns the population covariance as a ``float``, or ``default`` if there
aren't any matching rows.
Has one optional argument:
@ -198,18 +200,18 @@ field or an expression returning a numeric data. Both are required.
``RegrAvgX``
------------
.. class:: RegrAvgX(y, x, filter=None)
.. class:: RegrAvgX(y, x, filter=None, default=None)
Returns the average of the independent variable (``sum(x)/N``) as a
``float``, or ``None`` if there aren't any matching rows.
``float``, or ``default`` if there aren't any matching rows.
``RegrAvgY``
------------
.. class:: RegrAvgY(y, x, filter=None)
.. class:: RegrAvgY(y, x, filter=None, default=None)
Returns the average of the dependent variable (``sum(y)/N``) as a
``float``, or ``None`` if there aren't any matching rows.
``float``, or ``default`` if there aren't any matching rows.
``RegrCount``
-------------
@ -219,56 +221,60 @@ field or an expression returning a numeric data. Both are required.
Returns an ``int`` of the number of input rows in which both expressions
are not null.
.. note::
The ``default`` argument is not supported.
``RegrIntercept``
-----------------
.. class:: RegrIntercept(y, x, filter=None)
.. class:: RegrIntercept(y, x, filter=None, default=None)
Returns the y-intercept of the least-squares-fit linear equation determined
by the ``(x, y)`` pairs as a ``float``, or ``None`` if there aren't any
by the ``(x, y)`` pairs as a ``float``, or ``default`` if there aren't any
matching rows.
``RegrR2``
----------
.. class:: RegrR2(y, x, filter=None)
.. class:: RegrR2(y, x, filter=None, default=None)
Returns the square of the correlation coefficient as a ``float``, or
``None`` if there aren't any matching rows.
``default`` if there aren't any matching rows.
``RegrSlope``
-------------
.. class:: RegrSlope(y, x, filter=None)
.. class:: RegrSlope(y, x, filter=None, default=None)
Returns the slope of the least-squares-fit linear equation determined
by the ``(x, y)`` pairs as a ``float``, or ``None`` if there aren't any
by the ``(x, y)`` pairs as a ``float``, or ``default`` if there aren't any
matching rows.
``RegrSXX``
-----------
.. class:: RegrSXX(y, x, filter=None)
.. class:: RegrSXX(y, x, filter=None, default=None)
Returns ``sum(x^2) - sum(x)^2/N`` ("sum of squares" of the independent
variable) as a ``float``, or ``None`` if there aren't any matching rows.
variable) as a ``float``, or ``default`` if there aren't any matching rows.
``RegrSXY``
-----------
.. class:: RegrSXY(y, x, filter=None)
.. class:: RegrSXY(y, x, filter=None, default=None)
Returns ``sum(x*y) - sum(x) * sum(y)/N`` ("sum of products" of independent
times dependent variable) as a ``float``, or ``None`` if there aren't any
matching rows.
times dependent variable) as a ``float``, or ``default`` if there aren't
any matching rows.
``RegrSYY``
-----------
.. class:: RegrSYY(y, x, filter=None)
.. class:: RegrSYY(y, x, filter=None, default=None)
Returns ``sum(y^2) - sum(y)^2/N`` ("sum of squares" of the dependent
variable) as a ``float``, or ``None`` if there aren't any matching rows.
variable) as a ``float``, or ``default`` if there aren't any matching rows.
Usage examples
==============