Current File : //opt/hc_python/lib64/python3.8/site-packages/sqlalchemy/dialects/postgresql/array.py
# dialects/postgresql/array.py
# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: https://www.opensource.org/licenses/mit-license.php
# mypy: ignore-errors
from __future__ import annotations
import re
from typing import Any
from typing import Optional
from typing import TypeVar
from .operators import CONTAINED_BY
from .operators import CONTAINS
from .operators import OVERLAP
from ... import types as sqltypes
from ... import util
from ...sql import expression
from ...sql import operators
from ...sql._typing import _TypeEngineArgument
_T = TypeVar("_T", bound=Any)
def Any(other, arrexpr, operator=operators.eq):
"""A synonym for the ARRAY-level :meth:`.ARRAY.Comparator.any` method.
See that method for details.
"""
return arrexpr.any(other, operator)
def All(other, arrexpr, operator=operators.eq):
"""A synonym for the ARRAY-level :meth:`.ARRAY.Comparator.all` method.
See that method for details.
"""
return arrexpr.all(other, operator)
class array(expression.ExpressionClauseList[_T]):
"""A PostgreSQL ARRAY literal.
This is used to produce ARRAY literals in SQL expressions, e.g.::
from sqlalchemy.dialects.postgresql import array
from sqlalchemy.dialects import postgresql
from sqlalchemy import select, func
stmt = select(array([1,2]) + array([3,4,5]))
print(stmt.compile(dialect=postgresql.dialect()))
Produces the SQL::
SELECT ARRAY[%(param_1)s, %(param_2)s] ||
ARRAY[%(param_3)s, %(param_4)s, %(param_5)s]) AS anon_1
An instance of :class:`.array` will always have the datatype
:class:`_types.ARRAY`. The "inner" type of the array is inferred from
the values present, unless the ``type_`` keyword argument is passed::
array(['foo', 'bar'], type_=CHAR)
Multidimensional arrays are produced by nesting :class:`.array` constructs.
The dimensionality of the final :class:`_types.ARRAY`
type is calculated by
recursively adding the dimensions of the inner :class:`_types.ARRAY`
type::
stmt = select(
array([
array([1, 2]), array([3, 4]), array([column('q'), column('x')])
])
)
print(stmt.compile(dialect=postgresql.dialect()))
Produces::
SELECT ARRAY[ARRAY[%(param_1)s, %(param_2)s],
ARRAY[%(param_3)s, %(param_4)s], ARRAY[q, x]] AS anon_1
.. versionadded:: 1.3.6 added support for multidimensional array literals
.. seealso::
:class:`_postgresql.ARRAY`
"""
__visit_name__ = "array"
stringify_dialect = "postgresql"
inherit_cache = True
def __init__(self, clauses, **kw):
type_arg = kw.pop("type_", None)
super().__init__(operators.comma_op, *clauses, **kw)
self._type_tuple = [arg.type for arg in self.clauses]
main_type = (
type_arg
if type_arg is not None
else self._type_tuple[0] if self._type_tuple else sqltypes.NULLTYPE
)
if isinstance(main_type, ARRAY):
self.type = ARRAY(
main_type.item_type,
dimensions=(
main_type.dimensions + 1
if main_type.dimensions is not None
else 2
),
)
else:
self.type = ARRAY(main_type)
@property
def _select_iterable(self):
return (self,)
def _bind_param(self, operator, obj, _assume_scalar=False, type_=None):
if _assume_scalar or operator is operators.getitem:
return expression.BindParameter(
None,
obj,
_compared_to_operator=operator,
type_=type_,
_compared_to_type=self.type,
unique=True,
)
else:
return array(
[
self._bind_param(
operator, o, _assume_scalar=True, type_=type_
)
for o in obj
]
)
def self_group(self, against=None):
if against in (operators.any_op, operators.all_op, operators.getitem):
return expression.Grouping(self)
else:
return self
class ARRAY(sqltypes.ARRAY):
"""PostgreSQL ARRAY type.
The :class:`_postgresql.ARRAY` type is constructed in the same way
as the core :class:`_types.ARRAY` type; a member type is required, and a
number of dimensions is recommended if the type is to be used for more
than one dimension::
from sqlalchemy.dialects import postgresql
mytable = Table("mytable", metadata,
Column("data", postgresql.ARRAY(Integer, dimensions=2))
)
The :class:`_postgresql.ARRAY` type provides all operations defined on the
core :class:`_types.ARRAY` type, including support for "dimensions",
indexed access, and simple matching such as
:meth:`.types.ARRAY.Comparator.any` and
:meth:`.types.ARRAY.Comparator.all`. :class:`_postgresql.ARRAY`
class also
provides PostgreSQL-specific methods for containment operations, including
:meth:`.postgresql.ARRAY.Comparator.contains`
:meth:`.postgresql.ARRAY.Comparator.contained_by`, and
:meth:`.postgresql.ARRAY.Comparator.overlap`, e.g.::
mytable.c.data.contains([1, 2])
Indexed access is one-based by default, to match that of PostgreSQL;
for zero-based indexed access, set
:paramref:`_postgresql.ARRAY.zero_indexes`.
Additionally, the :class:`_postgresql.ARRAY`
type does not work directly in
conjunction with the :class:`.ENUM` type. For a workaround, see the
special type at :ref:`postgresql_array_of_enum`.
.. container:: topic
**Detecting Changes in ARRAY columns when using the ORM**
The :class:`_postgresql.ARRAY` type, when used with the SQLAlchemy ORM,
does not detect in-place mutations to the array. In order to detect
these, the :mod:`sqlalchemy.ext.mutable` extension must be used, using
the :class:`.MutableList` class::
from sqlalchemy.dialects.postgresql import ARRAY
from sqlalchemy.ext.mutable import MutableList
class SomeOrmClass(Base):
# ...
data = Column(MutableList.as_mutable(ARRAY(Integer)))
This extension will allow "in-place" changes such to the array
such as ``.append()`` to produce events which will be detected by the
unit of work. Note that changes to elements **inside** the array,
including subarrays that are mutated in place, are **not** detected.
Alternatively, assigning a new array value to an ORM element that
replaces the old one will always trigger a change event.
.. seealso::
:class:`_types.ARRAY` - base array type
:class:`_postgresql.array` - produces a literal array value.
"""
def __init__(
self,
item_type: _TypeEngineArgument[Any],
as_tuple: bool = False,
dimensions: Optional[int] = None,
zero_indexes: bool = False,
):
"""Construct an ARRAY.
E.g.::
Column('myarray', ARRAY(Integer))
Arguments are:
:param item_type: The data type of items of this array. Note that
dimensionality is irrelevant here, so multi-dimensional arrays like
``INTEGER[][]``, are constructed as ``ARRAY(Integer)``, not as
``ARRAY(ARRAY(Integer))`` or such.
:param as_tuple=False: Specify whether return results
should be converted to tuples from lists. DBAPIs such
as psycopg2 return lists by default. When tuples are
returned, the results are hashable.
:param dimensions: if non-None, the ARRAY will assume a fixed
number of dimensions. This will cause the DDL emitted for this
ARRAY to include the exact number of bracket clauses ``[]``,
and will also optimize the performance of the type overall.
Note that PG arrays are always implicitly "non-dimensioned",
meaning they can store any number of dimensions no matter how
they were declared.
:param zero_indexes=False: when True, index values will be converted
between Python zero-based and PostgreSQL one-based indexes, e.g.
a value of one will be added to all index values before passing
to the database.
"""
if isinstance(item_type, ARRAY):
raise ValueError(
"Do not nest ARRAY types; ARRAY(basetype) "
"handles multi-dimensional arrays of basetype"
)
if isinstance(item_type, type):
item_type = item_type()
self.item_type = item_type
self.as_tuple = as_tuple
self.dimensions = dimensions
self.zero_indexes = zero_indexes
class Comparator(sqltypes.ARRAY.Comparator):
"""Define comparison operations for :class:`_types.ARRAY`.
Note that these operations are in addition to those provided
by the base :class:`.types.ARRAY.Comparator` class, including
:meth:`.types.ARRAY.Comparator.any` and
:meth:`.types.ARRAY.Comparator.all`.
"""
def contains(self, other, **kwargs):
"""Boolean expression. Test if elements are a superset of the
elements of the argument array expression.
kwargs may be ignored by this operator but are required for API
conformance.
"""
return self.operate(CONTAINS, other, result_type=sqltypes.Boolean)
def contained_by(self, other):
"""Boolean expression. Test if elements are a proper subset of the
elements of the argument array expression.
"""
return self.operate(
CONTAINED_BY, other, result_type=sqltypes.Boolean
)
def overlap(self, other):
"""Boolean expression. Test if array has elements in common with
an argument array expression.
"""
return self.operate(OVERLAP, other, result_type=sqltypes.Boolean)
comparator_factory = Comparator
@property
def hashable(self):
return self.as_tuple
@property
def python_type(self):
return list
def compare_values(self, x, y):
return x == y
@util.memoized_property
def _against_native_enum(self):
return (
isinstance(self.item_type, sqltypes.Enum)
and self.item_type.native_enum
)
def literal_processor(self, dialect):
item_proc = self.item_type.dialect_impl(dialect).literal_processor(
dialect
)
if item_proc is None:
return None
def to_str(elements):
return f"ARRAY[{', '.join(elements)}]"
def process(value):
inner = self._apply_item_processor(
value, item_proc, self.dimensions, to_str
)
return inner
return process
def bind_processor(self, dialect):
item_proc = self.item_type.dialect_impl(dialect).bind_processor(
dialect
)
def process(value):
if value is None:
return value
else:
return self._apply_item_processor(
value, item_proc, self.dimensions, list
)
return process
def result_processor(self, dialect, coltype):
item_proc = self.item_type.dialect_impl(dialect).result_processor(
dialect, coltype
)
def process(value):
if value is None:
return value
else:
return self._apply_item_processor(
value,
item_proc,
self.dimensions,
tuple if self.as_tuple else list,
)
if self._against_native_enum:
super_rp = process
pattern = re.compile(r"^{(.*)}$")
def handle_raw_string(value):
inner = pattern.match(value).group(1)
return _split_enum_values(inner)
def process(value):
if value is None:
return value
# isinstance(value, str) is required to handle
# the case where a TypeDecorator for and Array of Enum is
# used like was required in sa < 1.3.17
return super_rp(
handle_raw_string(value)
if isinstance(value, str)
else value
)
return process
def _split_enum_values(array_string):
if '"' not in array_string:
# no escape char is present so it can just split on the comma
return array_string.split(",") if array_string else []
# handles quoted strings from:
# r'abc,"quoted","also\\\\quoted", "quoted, comma", "esc \" quot", qpr'
# returns
# ['abc', 'quoted', 'also\\quoted', 'quoted, comma', 'esc " quot', 'qpr']
text = array_string.replace(r"\"", "_$ESC_QUOTE$_")
text = text.replace(r"\\", "\\")
result = []
on_quotes = re.split(r'(")', text)
in_quotes = False
for tok in on_quotes:
if tok == '"':
in_quotes = not in_quotes
elif in_quotes:
result.append(tok.replace("_$ESC_QUOTE$_", '"'))
else:
result.extend(re.findall(r"([^\s,]+),?", tok))
return result
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