sqlalchemy-exc-dataerror.markdown

title: sqlalchemy.exc DataError Example Code category: page slug: sqlalchemy-exc-dataerror-examples sortorder: 500031035 toc: False sidebartitle: sqlalchemy.exc DataError meta: Example code for understanding how to use the DataError class from the sqlalchemy.exc module of the SQLAlchemy project.

DataError is a class within the sqlalchemy.exc module of the SQLAlchemy project.

ArgumentError, DatabaseError, IntegrityError, InvalidRequestError, NoInspectionAvailable, NoSuchTableError, OperationalError, ProgrammingError, and UnsupportedCompilationError are several other callables with code examples from the same sqlalchemy.exc package.

Example 1 from sqlalchemy-utils

sqlalchemy-utils (project documentation and PyPI package information) is a code library with various helper functions and new data types that make it easier to use SQLAlchemy when building projects that involve more specific storage requirements such as currency. The wide array of data types includes ranged values and aggregated attributes.

sqlalchemy-utils / sqlalchemy_utils / asserts.py

# asserts.py
from decimal import Decimal

import sqlalchemy as sa
from sqlalchemy.dialects.postgresql import ARRAY
~~from sqlalchemy.exc import DataError, IntegrityError


def _update_field(obj, field, value):
    session = sa.orm.object_session(obj)
    column = sa.inspect(obj.__class__).columns[field]
    query = column.table.update().values(**{column.key: value})
    session.execute(query)
    session.flush()


def _expect_successful_update(obj, field, value, reraise_exc):
    try:
        _update_field(obj, field, value)
    except (reraise_exc) as e:
        session = sa.orm.object_session(obj)
        session.rollback()
        assert False, str(e)


def _expect_failing_update(obj, field, value, expected_exc):
    try:
        _update_field(obj, field, value)
    except expected_exc:
        pass


## ... source file continues with no further DataError examples...