SQL functions which are known to SQLAlchemy with regards to database-specific
rendering, return types and argument behavior. Generic functions are invoked
like all SQL functions, using the func
attribute:
select(func.count()).select_from(sometable)
Note that any name not known to func
generates the function name as is
- there is no restriction on what SQL functions can be called, known or
unknown to SQLAlchemy, built-in or user defined. The section here only
describes those functions where SQLAlchemy already knows what argument and
return types are in use.
See also
Working with SQL Functions - in the SQLAlchemy 1.4 / 2.0 Tutorial
SQL function API, factories, and built-in functions.
Object Name | Description |
---|---|
Define a function in “ansi” format, which doesn’t render parenthesis. |
|
Support for the ARRAY_AGG function. |
|
The CHAR_LENGTH() SQL function. |
|
The SQL CONCAT() function, which concatenates strings. |
|
The ANSI COUNT aggregate function. With no arguments, emits COUNT *. |
|
Implement the |
|
Implement the |
|
The CURRENT_DATE() SQL function. |
|
The CURRENT_TIME() SQL function. |
|
The CURRENT_TIMESTAMP() SQL function. |
|
The CURRENT_USER() SQL function. |
|
Implement the |
|
Describe a named SQL function. |
|
Base for SQL function-oriented constructs. |
|
Define a ‘generic’ function. |
|
Implement the |
|
The localtime() SQL function. |
|
The localtimestamp() SQL function. |
|
The SQL MAX() aggregate function. |
|
The SQL MIN() aggregate function. |
|
Implement the |
|
Represent the ‘next value’, given a |
|
The SQL now() datetime function. |
|
Define a function where the return type is based on the sort
expression type as defined by the expression passed to the
|
|
Implement the |
|
Implement the |
|
Implement the |
|
The RANDOM() SQL function. |
|
Implement the |
|
|
Associate a callable with a particular func. name. |
Define a function whose return type is the same as its arguments. |
|
Implement the |
|
The SESSION_USER() SQL function. |
|
The SQL SUM() aggregate function. |
|
The SYSDATE() SQL function. |
|
The USER() SQL function. |
sqlalchemy.sql.functions.
AnsiFunction
(*args, **kwargs)¶Define a function in “ansi” format, which doesn’t render parenthesis.
Class signature
class sqlalchemy.sql.functions.AnsiFunction
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
Function
(name, *clauses, **kw)¶Describe a named SQL function.
The Function
object is typically generated from the
func
generation object.
*clauses¶ – list of column expressions that form the arguments of the SQL function call.
type_¶ – optional TypeEngine
datatype object that will be
used as the return value of the column expression generated by this
function call.
packagenames¶ –
a string which indicates package prefix names
to be prepended to the function name when the SQL is generated.
The func
generator creates these when it is called using
dotted format, e.g.:
func.mypackage.some_function(col1, col2)
See also
Working with SQL Functions - in the SQLAlchemy 1.4 / 2.0 Tutorial
func
- namespace which produces registered or ad-hoc
Function
instances.
GenericFunction
- allows creation of registered function
types.
Class signature
class sqlalchemy.sql.functions.Function
(sqlalchemy.sql.functions.FunctionElement
)
sqlalchemy.sql.functions.Function.
__init__
(name, *clauses, **kw)¶Construct a Function
.
The func
construct is normally used to construct
new Function
instances.
sqlalchemy.sql.functions.Function.
type
= NullType()¶A TypeEngine
object which refers to the SQL return
type represented by this SQL function.
This datatype may be configured when generating a
Function
object by passing the
Function.type_
parameter, e.g.:
>>> select(func.lower("some VALUE", type_=String))
The small number of built-in classes of Function
come
with a built-in datatype that’s appropriate to the class of function and
its arguments. For functions that aren’t known, the type defaults to the
“null type”.
sqlalchemy.sql.functions.
FunctionAsBinary
(fn, left_index, right_index)¶Class signature
class sqlalchemy.sql.functions.FunctionAsBinary
(sqlalchemy.sql.expression.BinaryExpression
)
sqlalchemy.sql.functions.
FunctionElement
(*clauses, **kwargs)¶Base for SQL function-oriented constructs.
See also
Functions - in the Core tutorial
Function
- named SQL function.
func
- namespace which produces registered or ad-hoc
Function
instances.
GenericFunction
- allows creation of registered function
types.
Class signature
class sqlalchemy.sql.functions.FunctionElement
(sqlalchemy.sql.expression.Executable
, sqlalchemy.sql.expression.ColumnElement
, sqlalchemy.sql.expression.FromClause
, sqlalchemy.sql.expression.Generative
)
sqlalchemy.sql.functions.FunctionElement.
__init__
(*clauses, **kwargs)¶Construct a FunctionElement
.
sqlalchemy.sql.functions.FunctionElement.
alias
(name=None)¶Produce a Alias
construct against this
FunctionElement
.
Tip
The FunctionElement.alias()
method is part of the
mechanism by which “table valued” SQL functions are created.
However, most use cases are covered by higher level methods on
FunctionElement
including
FunctionElement.table_valued()
, and
FunctionElement.column_valued()
.
This construct wraps the function in a named alias which
is suitable for the FROM clause, in the style accepted for example
by PostgreSQL. A column expression is also provided using the
special .column
attribute, which may
be used to refer to the output of the function as a scalar value
in the columns or where clause, for a backend such as PostgreSQL.
For a full table-valued expression, use the
FunctionElement.table_valued()
method first to
establish named columns.
e.g.:
>>> from sqlalchemy import func, select, column
>>> data_view = func.unnest([1, 2, 3]).alias("data_view")
>>> print(select(data_view.column))
SELECT data_view
FROM unnest(:unnest_1) AS data_view
The FunctionElement.column_valued()
method provides
a shortcut for the above pattern:
>>> data_view = func.unnest([1, 2, 3]).column_valued("data_view")
>>> print(select(data_view))
SELECT data_view
FROM unnest(:unnest_1) AS data_view
New in version 1.4.0b2: Added the .column
accessor
sqlalchemy.sql.functions.FunctionElement.
as_comparison
(left_index, right_index)¶Interpret this expression as a boolean comparison between two values.
This method is used for an ORM use case described at Custom operators based on SQL functions.
A hypothetical SQL function “is_equal()” which compares to values for equality would be written in the Core expression language as:
expr = func.is_equal("a", "b")
If “is_equal()” above is comparing “a” and “b” for equality, the
FunctionElement.as_comparison()
method would be invoked as:
expr = func.is_equal("a", "b").as_comparison(1, 2)
Where above, the integer value “1” refers to the first argument of the “is_equal()” function and the integer value “2” refers to the second.
This would create a BinaryExpression
that is equivalent to:
BinaryExpression("a", "b", operator=op.eq)
However, at the SQL level it would still render as “is_equal(‘a’, ‘b’)”.
The ORM, when it loads a related object or collection, needs to be able
to manipulate the “left” and “right” sides of the ON clause of a JOIN
expression. The purpose of this method is to provide a SQL function
construct that can also supply this information to the ORM, when used
with the relationship.primaryjoin
parameter. The
return value is a containment object called FunctionAsBinary
.
An ORM example is as follows:
class Venue(Base):
__tablename__ = 'venue'
id = Column(Integer, primary_key=True)
name = Column(String)
descendants = relationship(
"Venue",
primaryjoin=func.instr(
remote(foreign(name)), name + "/"
).as_comparison(1, 2) == 1,
viewonly=True,
order_by=name
)
Above, the “Venue” class can load descendant “Venue” objects by determining if the name of the parent Venue is contained within the start of the hypothetical descendant value’s name, e.g. “parent1” would match up to “parent1/child1”, but not to “parent2/child1”.
Possible use cases include the “materialized path” example given above, as well as making use of special SQL functions such as geometric functions to create join conditions.
New in version 1.3.
See also
Custom operators based on SQL functions - example use within the ORM
sqlalchemy.sql.functions.FunctionElement.
clauses
¶Return the underlying ClauseList
which contains
the arguments for this FunctionElement
.
sqlalchemy.sql.functions.FunctionElement.
column_valued
(name=None)¶Return this FunctionElement
as a column expression that
selects from itself as a FROM clause.
E.g.:
>>> from sqlalchemy import select, func
>>> gs = func.generate_series(1, 5, -1).column_valued()
>>> print(select(gs))
SELECT anon_1
FROM generate_series(:generate_series_1, :generate_series_2, :generate_series_3) AS anon_1
This is shorthand for:
gs = func.generate_series(1, 5, -1).alias().column
See also
Column Valued Functions - Table Valued Function as a Scalar Column - in the SQLAlchemy 1.4 / 2.0 Tutorial
Column Valued Functions - in the PostgreSQL documentation
sqlalchemy.sql.functions.FunctionElement.
columns
¶The set of columns exported by this FunctionElement
.
This is a placeholder collection that allows the function to be placed in the FROM clause of a statement:
>>> from sqlalchemy import column, select, func
>>> stmt = select(column('x'), column('y')).select_from(func.myfunction())
>>> print(stmt)
SELECT x, y FROM myfunction()
The above form is a legacy feature that is now superseded by the
fully capable FunctionElement.table_valued()
method; see that method for details.
See also
FunctionElement.table_valued()
- generates table-valued
SQL function expressions.
sqlalchemy.sql.functions.FunctionElement.
execute
()¶Execute this FunctionElement
against an embedded
‘bind’.
Deprecated since version 1.4: The FunctionElement.execute()
method is considered legacy as of the 1.x series of SQLAlchemy and will be removed in 2.0. All statement execution in SQLAlchemy 2.0 is performed by the Connection.execute()
method of Connection
, or in the ORM by the Session.execute()
method of Session
. (Background on SQLAlchemy 2.0 at: Migrating to SQLAlchemy 2.0)
This first calls FunctionElement.select()
to
produce a SELECT construct.
Note that FunctionElement
can be passed to
the Connectable.execute()
method of Connection
or Engine
.
sqlalchemy.sql.functions.FunctionElement.
filter
(*criterion)¶Produce a FILTER clause against this function.
Used against aggregate and window functions, for database backends that support the “FILTER” clause.
The expression:
func.count(1).filter(True)
is shorthand for:
from sqlalchemy import funcfilter
funcfilter(func.count(1), True)
New in version 1.0.0.
sqlalchemy.sql.functions.FunctionElement.
over
(partition_by=None, order_by=None, rows=None, range_=None)¶Produce an OVER clause against this function.
Used against aggregate or so-called “window” functions, for database backends that support window functions.
The expression:
func.row_number().over(order_by='x')
is shorthand for:
from sqlalchemy import over
over(func.row_number(), order_by='x')
See over()
for a full description.
sqlalchemy.sql.functions.FunctionElement.
scalar
()¶Execute this FunctionElement
against an embedded
‘bind’ and return a scalar value.
Deprecated since version 1.4: The FunctionElement.scalar()
method is considered legacy as of the 1.x series of SQLAlchemy and will be removed in 2.0. Scalar execution in SQLAlchemy 2.0 is performed by the Connection.scalar()
method of Connection
, or in the ORM by the Session.scalar()
method of Session
. (Background on SQLAlchemy 2.0 at: Migrating to SQLAlchemy 2.0)
This first calls FunctionElement.select()
to
produce a SELECT construct.
Note that FunctionElement
can be passed to
the Connectable.scalar()
method of Connection
or Engine
.
sqlalchemy.sql.functions.FunctionElement.
scalar_table_valued
(name, type_=None)¶Return a column expression that’s against this
FunctionElement
as a scalar
table-valued expression.
The returned expression is similar to that returned by a single column
accessed off of a FunctionElement.table_valued()
construct, except no FROM clause is generated; the function is rendered
in the similar way as a scalar subquery.
E.g.:
>>> from sqlalchemy import func, select
>>> fn = func.jsonb_each("{'k', 'v'}").scalar_table_valued("key")
>>> print(select(fn))
SELECT (jsonb_each(:jsonb_each_1)).key
New in version 1.4.0b2.
sqlalchemy.sql.functions.FunctionElement.
select
()¶Produce a select()
construct
against this FunctionElement
.
This is shorthand for:
s = select(function_element)
sqlalchemy.sql.functions.FunctionElement.
self_group
(against=None)¶Apply a ‘grouping’ to this ClauseElement
.
This method is overridden by subclasses to return a “grouping”
construct, i.e. parenthesis. In particular it’s used by “binary”
expressions to provide a grouping around themselves when placed into a
larger expression, as well as by select()
constructs when placed into the FROM clause of another
select()
. (Note that subqueries should be
normally created using the Select.alias()
method,
as many
platforms require nested SELECT statements to be named).
As expressions are composed together, the application of
self_group()
is automatic - end-user code should never
need to use this method directly. Note that SQLAlchemy’s
clause constructs take operator precedence into account -
so parenthesis might not be needed, for example, in
an expression like x OR (y AND z)
- AND takes precedence
over OR.
The base self_group()
method of
ClauseElement
just returns self.
sqlalchemy.sql.functions.FunctionElement.
table_valued
(*expr, **kw)¶Return a TableValuedAlias
representation of this
FunctionElement
with table-valued expressions added.
e.g.:
>>> fn = (
... func.generate_series(1, 5).
... table_valued("value", "start", "stop", "step")
... )
>>> print(select(fn))
SELECT anon_1.value, anon_1.start, anon_1.stop, anon_1.step
FROM generate_series(:generate_series_1, :generate_series_2) AS anon_1
>>> print(select(fn.c.value, fn.c.stop).where(fn.c.value > 2))
SELECT anon_1.value, anon_1.stop
FROM generate_series(:generate_series_1, :generate_series_2) AS anon_1
WHERE anon_1.value > :value_1
A WITH ORDINALITY expression may be generated by passing the keyword argument “with_ordinality”:
>>> fn = func.generate_series(4, 1, -1).table_valued("gen", with_ordinality="ordinality")
>>> print(select(fn))
SELECT anon_1.gen, anon_1.ordinality
FROM generate_series(:generate_series_1, :generate_series_2, :generate_series_3) WITH ORDINALITY AS anon_1
*expr¶ – A series of string column names that will be added to the
.c
collection of the resulting TableValuedAlias
construct as columns. column()
objects with or without
datatypes may also be used.
name¶ – optional name to assign to the alias name that’s generated. If omitted, a unique anonymizing name is used.
with_ordinality¶ – string name that when present results in the
WITH ORDINALITY
clause being added to the alias, and the given
string name will be added as a column to the .c collection
of the resulting TableValuedAlias
.
New in version 1.4.0b2.
See also
Table-Valued Functions - in the SQLAlchemy 1.4 / 2.0 Tutorial
Table-Valued Functions - in the PostgreSQL documentation
FunctionElement.scalar_table_valued()
- variant of
FunctionElement.table_valued()
which delivers the
complete table valued expression as a scalar column expression
FunctionElement.column_valued()
TableValuedAlias.render_derived()
- renders the alias
using a derived column clause, e.g. AS name(col1, col2, ...)
sqlalchemy.sql.functions.FunctionElement.
within_group
(*order_by)¶Produce a WITHIN GROUP (ORDER BY expr) clause against this function.
Used against so-called “ordered set aggregate” and “hypothetical
set aggregate” functions, including percentile_cont
,
rank
, dense_rank
, etc.
See within_group()
for a full description.
New in version 1.1.
See also
Special Modifiers WITHIN GROUP, FILTER - in the SQLAlchemy 1.4 / 2.0 Tutorial
sqlalchemy.sql.functions.FunctionElement.
within_group_type
(within_group)¶For types that define their return type as based on the criteria
within a WITHIN GROUP (ORDER BY) expression, called by the
WithinGroup
construct.
Returns None by default, in which case the function’s normal .type
is used.
sqlalchemy.sql.functions.
GenericFunction
(*args, **kwargs)¶Define a ‘generic’ function.
A generic function is a pre-established Function
class that is instantiated automatically when called
by name from the func
attribute. Note that
calling any name from func
has the effect that
a new Function
instance is created automatically,
given that name. The primary use case for defining
a GenericFunction
class is so that a function
of a particular name may be given a fixed return type.
It can also include custom argument parsing schemes as well
as additional methods.
Subclasses of GenericFunction
are automatically
registered under the name of the class. For
example, a user-defined function as_utc()
would
be available immediately:
from sqlalchemy.sql.functions import GenericFunction
from sqlalchemy.types import DateTime
class as_utc(GenericFunction):
type = DateTime
print(select(func.as_utc()))
User-defined generic functions can be organized into
packages by specifying the “package” attribute when defining
GenericFunction
. Third party libraries
containing many functions may want to use this in order
to avoid name conflicts with other systems. For example,
if our as_utc()
function were part of a package
“time”:
class as_utc(GenericFunction):
type = DateTime
package = "time"
The above function would be available from func
using the package name time
:
print(select(func.time.as_utc()))
A final option is to allow the function to be accessed
from one name in func
but to render as a different name.
The identifier
attribute will override the name used to
access the function as loaded from func
, but will retain
the usage of name
as the rendered name:
class GeoBuffer(GenericFunction):
type = Geometry
package = "geo"
name = "ST_Buffer"
identifier = "buffer"
The above function will render as follows:
>>> print(func.geo.buffer())
ST_Buffer()
The name will be rendered as is, however without quoting unless the name
contains special characters that require quoting. To force quoting
on or off for the name, use the quoted_name
construct:
from sqlalchemy.sql import quoted_name
class GeoBuffer(GenericFunction):
type = Geometry
package = "geo"
name = quoted_name("ST_Buffer", True)
identifier = "buffer"
The above function will render as:
>>> print(func.geo.buffer())
"ST_Buffer"()
New in version 1.3.13: The quoted_name
construct is now
recognized for quoting when used with the “name” attribute of the
object, so that quoting can be forced on or off for the function
name.
Class signature
class sqlalchemy.sql.functions.GenericFunction
(sqlalchemy.sql.functions.Function
)
sqlalchemy.sql.functions.
OrderedSetAgg
(*args, **kwargs)¶Define a function where the return type is based on the sort
expression type as defined by the expression passed to the
FunctionElement.within_group()
method.
Class signature
class sqlalchemy.sql.functions.OrderedSetAgg
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.OrderedSetAgg.
within_group_type
(within_group)¶For types that define their return type as based on the criteria
within a WITHIN GROUP (ORDER BY) expression, called by the
WithinGroup
construct.
Returns None by default, in which case the function’s normal .type
is used.
sqlalchemy.sql.functions.
ReturnTypeFromArgs
(*args, **kwargs)¶Define a function whose return type is the same as its arguments.
Class signature
class sqlalchemy.sql.functions.ReturnTypeFromArgs
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
ScalarFunctionColumn
(fn, name, type_=None)¶Class signature
class sqlalchemy.sql.functions.ScalarFunctionColumn
(sqlalchemy.sql.expression.NamedColumn
)
sqlalchemy.sql.functions.
array_agg
(*args, **kwargs)¶Support for the ARRAY_AGG function.
The func.array_agg(expr)
construct returns an expression of
type ARRAY
.
e.g.:
stmt = select(func.array_agg(table.c.values)[2:5])
New in version 1.1.
See also
array_agg()
- PostgreSQL-specific version that
returns ARRAY
, which has PG-specific operators
added.
Class signature
class sqlalchemy.sql.functions.array_agg
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.array_agg.
type
¶alias of sqlalchemy.sql.sqltypes.ARRAY
sqlalchemy.sql.functions.
char_length
(arg, **kwargs)¶The CHAR_LENGTH() SQL function.
Class signature
class sqlalchemy.sql.functions.char_length
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.char_length.
type
¶alias of sqlalchemy.sql.sqltypes.Integer
sqlalchemy.sql.functions.
coalesce
(*args, **kwargs)¶Class signature
class sqlalchemy.sql.functions.coalesce
(sqlalchemy.sql.functions.ReturnTypeFromArgs
)
sqlalchemy.sql.functions.
concat
(*args, **kwargs)¶The SQL CONCAT() function, which concatenates strings.
E.g.:
>>> print(select(func.concat('a', 'b')))
SELECT concat(:concat_2, :concat_3) AS concat_1
String concatenation in SQLAlchemy is more commonly available using the
Python +
operator with string datatypes, which will render a
backend-specific concatenation operator, such as
>>> print(select(literal("a") + "b"))
SELECT :param_1 || :param_2 AS anon_1
Class signature
class sqlalchemy.sql.functions.concat
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.concat.
type
¶alias of sqlalchemy.sql.sqltypes.String
sqlalchemy.sql.functions.
count
(expression=None, **kwargs)¶The ANSI COUNT aggregate function. With no arguments, emits COUNT *.
E.g.:
from sqlalchemy import func
from sqlalchemy import select
from sqlalchemy import table, column
my_table = table('some_table', column('id'))
stmt = select(func.count()).select_from(my_table)
Executing stmt
would emit:
SELECT count(*) AS count_1
FROM some_table
Class signature
class sqlalchemy.sql.functions.count
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.count.
type
¶alias of sqlalchemy.sql.sqltypes.Integer
sqlalchemy.sql.functions.
cube
(*args, **kwargs)¶Implement the CUBE
grouping operation.
This function is used as part of the GROUP BY of a statement,
e.g. Select.group_by()
:
stmt = select(
func.sum(table.c.value), table.c.col_1, table.c.col_2
).group_by(func.cube(table.c.col_1, table.c.col_2))
New in version 1.2.
Class signature
class sqlalchemy.sql.functions.cube
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
cume_dist
(*args, **kwargs)¶Implement the cume_dist
hypothetical-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is Numeric
.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.cume_dist
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
current_date
(*args, **kwargs)¶The CURRENT_DATE() SQL function.
Class signature
class sqlalchemy.sql.functions.current_date
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.current_date.
type
¶alias of sqlalchemy.sql.sqltypes.Date
sqlalchemy.sql.functions.
current_time
(*args, **kwargs)¶The CURRENT_TIME() SQL function.
Class signature
class sqlalchemy.sql.functions.current_time
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.current_time.
type
¶alias of sqlalchemy.sql.sqltypes.Time
sqlalchemy.sql.functions.
current_timestamp
(*args, **kwargs)¶The CURRENT_TIMESTAMP() SQL function.
Class signature
class sqlalchemy.sql.functions.current_timestamp
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.current_timestamp.
type
¶alias of sqlalchemy.sql.sqltypes.DateTime
sqlalchemy.sql.functions.
current_user
(*args, **kwargs)¶The CURRENT_USER() SQL function.
Class signature
class sqlalchemy.sql.functions.current_user
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.current_user.
type
¶alias of sqlalchemy.sql.sqltypes.String
sqlalchemy.sql.functions.
dense_rank
(*args, **kwargs)¶Implement the dense_rank
hypothetical-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is Integer
.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.dense_rank
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
grouping_sets
(*args, **kwargs)¶Implement the GROUPING SETS
grouping operation.
This function is used as part of the GROUP BY of a statement,
e.g. Select.group_by()
:
stmt = select(
func.sum(table.c.value), table.c.col_1, table.c.col_2
).group_by(func.grouping_sets(table.c.col_1, table.c.col_2))
In order to group by multiple sets, use the tuple_()
construct:
from sqlalchemy import tuple_
stmt = select(
func.sum(table.c.value),
table.c.col_1, table.c.col_2,
table.c.col_3
).group_by(
func.grouping_sets(
tuple_(table.c.col_1, table.c.col_2),
tuple_(table.c.value, table.c.col_3),
)
)
New in version 1.2.
Class signature
class sqlalchemy.sql.functions.grouping_sets
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
localtime
(*args, **kwargs)¶The localtime() SQL function.
Class signature
class sqlalchemy.sql.functions.localtime
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.localtime.
type
¶alias of sqlalchemy.sql.sqltypes.DateTime
sqlalchemy.sql.functions.
localtimestamp
(*args, **kwargs)¶The localtimestamp() SQL function.
Class signature
class sqlalchemy.sql.functions.localtimestamp
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.localtimestamp.
type
¶alias of sqlalchemy.sql.sqltypes.DateTime
sqlalchemy.sql.functions.
max
(*args, **kwargs)¶The SQL MAX() aggregate function.
Class signature
class sqlalchemy.sql.functions.max
(sqlalchemy.sql.functions.ReturnTypeFromArgs
)
sqlalchemy.sql.functions.
min
(*args, **kwargs)¶The SQL MIN() aggregate function.
Class signature
class sqlalchemy.sql.functions.min
(sqlalchemy.sql.functions.ReturnTypeFromArgs
)
sqlalchemy.sql.functions.
mode
(*args, **kwargs)¶Implement the mode
ordered-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is the same as the sort expression.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.mode
(sqlalchemy.sql.functions.OrderedSetAgg
)
sqlalchemy.sql.functions.
next_value
(seq, **kw)¶Represent the ‘next value’, given a Sequence
as its single argument.
Compiles into the appropriate function on each backend, or will raise NotImplementedError if used on a backend that does not provide support for sequences.
Class signature
class sqlalchemy.sql.functions.next_value
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.next_value.
compare
(other, **kw)¶Compare this ClauseElement
to
the given ClauseElement
.
Subclasses should override the default behavior, which is a straight identity comparison.
**kw are arguments consumed by subclass compare()
methods and
may be used to modify the criteria for comparison
(see ColumnElement
).
sqlalchemy.sql.functions.
now
(*args, **kwargs)¶The SQL now() datetime function.
SQLAlchemy dialects will usually render this particular function
in a backend-specific way, such as rendering it as CURRENT_TIMESTAMP
.
Class signature
class sqlalchemy.sql.functions.now
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.now.
type
¶alias of sqlalchemy.sql.sqltypes.DateTime
sqlalchemy.sql.functions.
percent_rank
(*args, **kwargs)¶Implement the percent_rank
hypothetical-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is Numeric
.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.percent_rank
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
percentile_cont
(*args, **kwargs)¶Implement the percentile_cont
ordered-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is the same as the sort expression,
or if the arguments are an array, an ARRAY
of the sort
expression’s type.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.percentile_cont
(sqlalchemy.sql.functions.OrderedSetAgg
)
sqlalchemy.sql.functions.
percentile_disc
(*args, **kwargs)¶Implement the percentile_disc
ordered-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is the same as the sort expression,
or if the arguments are an array, an ARRAY
of the sort
expression’s type.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.percentile_disc
(sqlalchemy.sql.functions.OrderedSetAgg
)
sqlalchemy.sql.functions.
random
(*args, **kwargs)¶The RANDOM() SQL function.
Class signature
class sqlalchemy.sql.functions.random
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
rank
(*args, **kwargs)¶Implement the rank
hypothetical-set aggregate function.
This function must be used with the FunctionElement.within_group()
modifier to supply a sort expression to operate upon.
The return type of this function is Integer
.
New in version 1.1.
Class signature
class sqlalchemy.sql.functions.rank
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
register_function
(identifier, fn, package='_default')¶Associate a callable with a particular func. name.
This is normally called by _GenericMeta, but is also
available by itself so that a non-Function construct
can be associated with the func
accessor (i.e.
CAST, EXTRACT).
sqlalchemy.sql.functions.
rollup
(*args, **kwargs)¶Implement the ROLLUP
grouping operation.
This function is used as part of the GROUP BY of a statement,
e.g. Select.group_by()
:
stmt = select(
func.sum(table.c.value), table.c.col_1, table.c.col_2
).group_by(func.rollup(table.c.col_1, table.c.col_2))
New in version 1.2.
Class signature
class sqlalchemy.sql.functions.rollup
(sqlalchemy.sql.functions.GenericFunction
)
sqlalchemy.sql.functions.
session_user
(*args, **kwargs)¶The SESSION_USER() SQL function.
Class signature
class sqlalchemy.sql.functions.session_user
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.session_user.
type
¶alias of sqlalchemy.sql.sqltypes.String
sqlalchemy.sql.functions.
sum
(*args, **kwargs)¶The SQL SUM() aggregate function.
Class signature
class sqlalchemy.sql.functions.sum
(sqlalchemy.sql.functions.ReturnTypeFromArgs
)
sqlalchemy.sql.functions.
sysdate
(*args, **kwargs)¶The SYSDATE() SQL function.
Class signature
class sqlalchemy.sql.functions.sysdate
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.sysdate.
type
¶alias of sqlalchemy.sql.sqltypes.DateTime
sqlalchemy.sql.functions.
user
(*args, **kwargs)¶The USER() SQL function.
Class signature
class sqlalchemy.sql.functions.user
(sqlalchemy.sql.functions.AnsiFunction
)
sqlalchemy.sql.functions.user.
type
¶alias of sqlalchemy.sql.sqltypes.String
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