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Direktori : /opt/cloudlinux/venv/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/ |
Current File : //opt/cloudlinux/venv/lib/python3.11/site-packages/sqlalchemy/dialects/mysql/dml.py |
from ... import exc from ... import util from ...sql.base import _generative from ...sql.dml import Insert as StandardInsert from ...sql.elements import ClauseElement from ...sql.expression import alias from ...util.langhelpers import public_factory __all__ = ("Insert", "insert") class Insert(StandardInsert): """MySQL-specific implementation of INSERT. Adds methods for MySQL-specific syntaxes such as ON DUPLICATE KEY UPDATE. The :class:`~.mysql.Insert` object is created using the :func:`sqlalchemy.dialects.mysql.insert` function. .. versionadded:: 1.2 """ @property def inserted(self): """Provide the "inserted" namespace for an ON DUPLICATE KEY UPDATE statement MySQL's ON DUPLICATE KEY UPDATE clause allows reference to the row that would be inserted, via a special function called ``VALUES()``. This attribute provides all columns in this row to be referenceable such that they will render within a ``VALUES()`` function inside the ON DUPLICATE KEY UPDATE clause. The attribute is named ``.inserted`` so as not to conflict with the existing :meth:`_expression.Insert.values` method. .. seealso:: :ref:`mysql_insert_on_duplicate_key_update` - example of how to use :attr:`_expression.Insert.inserted` """ return self.inserted_alias.columns @util.memoized_property def inserted_alias(self): return alias(self.table, name="inserted") @_generative def on_duplicate_key_update(self, *args, **kw): r""" Specifies the ON DUPLICATE KEY UPDATE clause. :param \**kw: Column keys linked to UPDATE values. The values may be any SQL expression or supported literal Python values. .. warning:: This dictionary does **not** take into account Python-specified default UPDATE values or generation functions, e.g. those specified using :paramref:`_schema.Column.onupdate`. These values will not be exercised for an ON DUPLICATE KEY UPDATE style of UPDATE, unless values are manually specified here. :param \*args: As an alternative to passing key/value parameters, a dictionary or list of 2-tuples can be passed as a single positional argument. Passing a single dictionary is equivalent to the keyword argument form:: insert().on_duplicate_key_update({"name": "some name"}) Passing a list of 2-tuples indicates that the parameter assignments in the UPDATE clause should be ordered as sent, in a manner similar to that described for the :class:`_expression.Update` construct overall in :ref:`updates_order_parameters`:: insert().on_duplicate_key_update( [("name", "some name"), ("value", "some value")]) .. versionchanged:: 1.3 parameters can be specified as a dictionary or list of 2-tuples; the latter form provides for parameter ordering. .. versionadded:: 1.2 .. seealso:: :ref:`mysql_insert_on_duplicate_key_update` """ if args and kw: raise exc.ArgumentError( "Can't pass kwargs and positional arguments simultaneously" ) if args: if len(args) > 1: raise exc.ArgumentError( "Only a single dictionary or list of tuples " "is accepted positionally." ) values = args[0] else: values = kw inserted_alias = getattr(self, "inserted_alias", None) self._post_values_clause = OnDuplicateClause(inserted_alias, values) return self insert = public_factory( Insert, ".dialects.mysql.insert", ".dialects.mysql.Insert" ) class OnDuplicateClause(ClauseElement): __visit_name__ = "on_duplicate_key_update" _parameter_ordering = None def __init__(self, inserted_alias, update): self.inserted_alias = inserted_alias # auto-detect that parameters should be ordered. This is copied from # Update._proces_colparams(), however we don't look for a special flag # in this case since we are not disambiguating from other use cases as # we are in Update.values(). if isinstance(update, list) and ( update and isinstance(update[0], tuple) ): self._parameter_ordering = [key for key, value in update] update = dict(update) if not update or not isinstance(update, dict): raise ValueError("update parameter must be a non-empty dictionary") self.update = update