Exceptions used with SQLAlchemy.
The base exception class is SQLAlchemyError. Exceptions which are
raised as a result of DBAPI exceptions are all subclasses of
DBAPIError.
sqlalchemy.exc.AmbiguousForeignKeysError(*arg, **kw)¶Raised when more than one foreign key matching can be located between two selectables during a join.
sqlalchemy.exc.ArgumentError(*arg, **kw)¶Raised when an invalid or conflicting function argument is supplied.
This error generally corresponds to construction time state errors.
sqlalchemy.exc.CircularDependencyError(message, cycles, edges, msg=None, code=None)¶Raised by topological sorts when a circular dependency is detected.
There are two scenarios where this error occurs:
post_update flag described at Rows that point to themselves / Mutually Dependent Rows can resolve
this cycle.MetaData.sorted_tables operation, two ForeignKey
or ForeignKeyConstraint objects mutually refer to each
other. Apply the use_alter=True flag to one or both,
see Creating/Dropping Foreign Key Constraints via ALTER.sqlalchemy.exc.CompileError(*arg, **kw)¶Raised when an error occurs during SQL compilation
sqlalchemy.exc.DBAPIError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Raised when the execution of a database operation fails.
Wraps exceptions raised by the DB-API underlying the
database operation. Driver-specific implementations of the standard
DB-API exception types are wrapped by matching sub-types of SQLAlchemy’s
DBAPIError when possible. DB-API’s Error type maps to
DBAPIError in SQLAlchemy, otherwise the names are identical. Note
that there is no guarantee that different DB-API implementations will
raise the same exception type for any given error condition.
DBAPIError features statement
and params attributes which supply context
regarding the specifics of the statement which had an issue, for the
typical case when the error was raised within the context of
emitting a SQL statement.
The wrapped exception object is available in the
orig attribute. Its type and properties are
DB-API implementation specific.
sqlalchemy.exc.DataError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API DataError.
sqlalchemy.exc.DatabaseError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API DatabaseError.
sqlalchemy.exc.DisconnectionError(*arg, **kw)¶A disconnect is detected on a raw DB-API connection.
This error is raised and consumed internally by a connection pool. It can
be raised by the PoolEvents.checkout() event so that the host pool
forces a retry; the exception will be caught three times in a row before
the pool gives up and raises InvalidRequestError
regarding the connection attempt.
sqlalchemy.exc.DontWrapMixin¶A mixin class which, when applied to a user-defined Exception class,
will not be wrapped inside of StatementError if the error is
emitted within the process of executing a statement.
E.g.:
from sqlalchemy.exc import DontWrapMixin
class MyCustomException(Exception, DontWrapMixin):
pass
class MySpecialType(TypeDecorator):
impl = String
def process_bind_param(self, value, dialect):
if value == 'invalid':
raise MyCustomException("invalid!")sqlalchemy.exc.IdentifierError(*arg, **kw)¶Raised when a schema name is beyond the max character limit
sqlalchemy.exc.IntegrityError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API IntegrityError.
sqlalchemy.exc.InterfaceError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API InterfaceError.
sqlalchemy.exc.InternalError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API InternalError.
sqlalchemy.exc.InvalidRequestError(*arg, **kw)¶SQLAlchemy was asked to do something it can’t do.
This error generally corresponds to runtime state errors.
sqlalchemy.exc.InvalidatePoolError(*arg, **kw)¶Raised when the connection pool should invalidate all stale connections.
A subclass of DisconnectionError that indicates that the
disconnect situation encountered on the connection probably means the
entire pool should be invalidated, as the database has been restarted.
This exception will be handled otherwise the same way as
DisconnectionError, allowing three attempts to reconnect
before giving up.
New in version 1.2.
sqlalchemy.exc.NoForeignKeysError(*arg, **kw)¶Raised when no foreign keys can be located between two selectables during a join.
sqlalchemy.exc.NoInspectionAvailable(*arg, **kw)¶A subject passed to sqlalchemy.inspection.inspect() produced
no context for inspection.
sqlalchemy.exc.NoReferenceError(*arg, **kw)¶Raised by ForeignKey to indicate a reference cannot be resolved.
sqlalchemy.exc.NoReferencedColumnError(message, tname, cname)¶Raised by ForeignKey when the referred Column cannot be
located.
sqlalchemy.exc.NoReferencedTableError(message, tname)¶Raised by ForeignKey when the referred Table cannot be
located.
sqlalchemy.exc.NoSuchColumnError¶A nonexistent column is requested from a RowProxy.
sqlalchemy.exc.NoSuchModuleError(*arg, **kw)¶Raised when a dynamically-loaded module (usually a database dialect) of a particular name cannot be located.
sqlalchemy.exc.NoSuchTableError(*arg, **kw)¶Table does not exist or is not visible to a connection.
sqlalchemy.exc.NotSupportedError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API NotSupportedError.
sqlalchemy.exc.ObjectNotExecutableError(target)¶Raised when an object is passed to .execute() that can’t be executed as SQL.
New in version 1.1.
sqlalchemy.exc.OperationalError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API OperationalError.
sqlalchemy.exc.ProgrammingError(statement, params, orig, hide_parameters=False, connection_invalidated=False, code=None, ismulti=None)¶Wraps a DB-API ProgrammingError.
sqlalchemy.exc.ResourceClosedError(*arg, **kw)¶An operation was requested from a connection, cursor, or other object that’s in a closed state.
sqlalchemy.exc.SADeprecationWarning¶Issued once per usage of a deprecated API.
sqlalchemy.exc.SAPendingDeprecationWarning¶Issued once per usage of a deprecated API.
sqlalchemy.exc.SAWarning¶Issued at runtime.
sqlalchemy.exc.SQLAlchemyError(*arg, **kw)¶Generic error class.
sqlalchemy.exc.StatementError(message, statement, params, orig, hide_parameters=False, code=None, ismulti=None)¶An error occurred during execution of a SQL statement.
StatementError wraps the exception raised
during execution, and features statement
and params attributes which supply context regarding
the specifics of the statement which had an issue.
The wrapped exception object is available in
the orig attribute.
orig = None¶The DBAPI exception object.
params = None¶The parameter list being used when this exception occurred.
statement = None¶The string SQL statement being invoked when this exception occurred.
sqlalchemy.exc.TimeoutError(*arg, **kw)¶Raised when a connection pool times out on getting a connection.
sqlalchemy.exc.UnboundExecutionError(*arg, **kw)¶SQL was attempted without a database connection to execute it on.
sqlalchemy.exc.UnreflectableTableError(*arg, **kw)¶Table exists but can’t be reflected for some reason.
New in version 1.2.
sqlalchemy.exc.UnsupportedCompilationError(compiler, element_type)¶Raised when an operation is not supported by the given compiler.