Core Exceptions
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.
exception sqlalchemy.exc.AmbiguousForeignKeysError
Raised when more than one foreign key matching can be located between two selectables during a join.
Class signature
class sqlalchemy.exc.AmbiguousForeignKeysError (sqlalchemy.exc.ArgumentError)
exception sqlalchemy.exc.ArgumentError
Raised when an invalid or conflicting function argument is supplied.
This error generally corresponds to construction time state errors.
Class signature
class sqlalchemy.exc.ArgumentError (sqlalchemy.exc.SQLAlchemyError)
exception sqlalchemy.exc.AwaitRequired
Error raised by the async greenlet spawn if no async operation was awaited when it required one.
Class signature
class sqlalchemy.exc.AwaitRequired (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.Base20DeprecationWarning
Issued for usage of APIs specifically deprecated or legacy in SQLAlchemy 2.0.
See also
The <some function> in SQLAlchemy 2.0 will no longer <something>.
SQLAlchemy 2.0 Deprecations Mode
Class signature
class sqlalchemy.exc.Base20DeprecationWarning (sqlalchemy.exc.SADeprecationWarning)
attribute sqlalchemy.exc.Base20DeprecationWarning.deprecated_since: Optional[str] = ‘1.4’
Indicates the version that started raising this deprecation warning
exception sqlalchemy.exc.CircularDependencyError
Raised by topological sorts when a circular dependency is detected.
There are two scenarios where this error occurs:
In a Session flush operation, if two objects are mutually dependent on each other, they can not be inserted or deleted via INSERT or DELETE statements alone; an UPDATE will be needed to post-associate or pre-deassociate one of the foreign key constrained values. The
post_update
flag described at Rows that point to themselves / Mutually Dependent Rows can resolve this cycle.In a 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.
Class signature
class sqlalchemy.exc.CircularDependencyError (sqlalchemy.exc.SQLAlchemyError)
- method sqlalchemy.exc.CircularDependencyError.__init__(message: str, cycles: Any, edges: Any, msg: Optional[str] = None, code: Optional[str] = None)
exception sqlalchemy.exc.CompileError
Raised when an error occurs during SQL compilation
Class signature
class sqlalchemy.exc.CompileError (sqlalchemy.exc.SQLAlchemyError)
exception sqlalchemy.exc.ConstraintColumnNotFoundError
raised when a constraint refers to a string column name that is not present in the table being constrained.
New in version 2.0.
Class signature
class sqlalchemy.exc.ConstraintColumnNotFoundError (sqlalchemy.exc.ArgumentError)
exception sqlalchemy.exc.DBAPIError
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 StatementError.statement and StatementError.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 StatementError.orig attribute. Its type and properties are DB-API implementation specific.
Class signature
class sqlalchemy.exc.DBAPIError (sqlalchemy.exc.StatementError)
- method sqlalchemy.exc.DBAPIError.__init__(statement: Optional[str], params: Optional[_AnyExecuteParams], orig: BaseException, hide_parameters: bool = False, connection_invalidated: bool = False, code: Optional[str] = None, ismulti: Optional[bool] = None)
exception sqlalchemy.exc.DataError
Wraps a DB-API DataError.
Class signature
class sqlalchemy.exc.DataError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.DatabaseError
Wraps a DB-API DatabaseError.
Class signature
class sqlalchemy.exc.DatabaseError (sqlalchemy.exc.DBAPIError)
exception sqlalchemy.exc.DisconnectionError
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.
Class signature
class sqlalchemy.exc.DisconnectionError (sqlalchemy.exc.SQLAlchemyError)
Object Name | Description |
---|---|
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. | |
helper which adds ‘code’ as an attribute and ‘_code_str’ as a method |
class 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!")
exception sqlalchemy.exc.DuplicateColumnError
a Column is being added to a Table that would replace another Column, without appropriate parameters to allow this in place.
New in version 2.0.0b4.
Class signature
class sqlalchemy.exc.DuplicateColumnError (sqlalchemy.exc.ArgumentError)
class sqlalchemy.exc.HasDescriptionCode
helper which adds ‘code’ as an attribute and ‘_code_str’ as a method
exception sqlalchemy.exc.IdentifierError
Raised when a schema name is beyond the max character limit
Class signature
class sqlalchemy.exc.IdentifierError (sqlalchemy.exc.SQLAlchemyError)
exception sqlalchemy.exc.IllegalStateChangeError
An object that tracks state encountered an illegal state change of some kind.
New in version 2.0.
Class signature
class sqlalchemy.exc.IllegalStateChangeError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.IntegrityError
Wraps a DB-API IntegrityError.
Class signature
class sqlalchemy.exc.IntegrityError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.InterfaceError
Wraps a DB-API InterfaceError.
Class signature
class sqlalchemy.exc.InterfaceError (sqlalchemy.exc.DBAPIError)
exception sqlalchemy.exc.InternalError
Wraps a DB-API InternalError.
Class signature
class sqlalchemy.exc.InternalError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.InvalidRequestError
SQLAlchemy was asked to do something it can’t do.
This error generally corresponds to runtime state errors.
Class signature
class sqlalchemy.exc.InvalidRequestError (sqlalchemy.exc.SQLAlchemyError)
exception sqlalchemy.exc.InvalidatePoolError
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.
Class signature
class sqlalchemy.exc.InvalidatePoolError (sqlalchemy.exc.DisconnectionError)
exception sqlalchemy.exc.LegacyAPIWarning
indicates an API that is in ‘legacy’ status, a long term deprecation.
Class signature
class sqlalchemy.exc.LegacyAPIWarning (sqlalchemy.exc.Base20DeprecationWarning)
exception sqlalchemy.exc.MissingGreenlet
Error raised by the async greenlet await_ if called while not inside the greenlet spawn context.
Class signature
class sqlalchemy.exc.MissingGreenlet (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.MovedIn20Warning
Subtype of RemovedIn20Warning to indicate an API that moved only.
Class signature
class sqlalchemy.exc.MovedIn20Warning (sqlalchemy.exc.Base20DeprecationWarning)
exception sqlalchemy.exc.MultipleResultsFound
A single database result was required but more than one were found.
Changed in version 1.4: This exception is now part of the sqlalchemy.exc
module in Core, moved from the ORM. The symbol remains importable from sqlalchemy.orm.exc
.
Class signature
class sqlalchemy.exc.MultipleResultsFound (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.NoForeignKeysError
Raised when no foreign keys can be located between two selectables during a join.
Class signature
class sqlalchemy.exc.NoForeignKeysError (sqlalchemy.exc.ArgumentError)
exception sqlalchemy.exc.NoInspectionAvailable
A subject passed to sqlalchemy.inspection.inspect()
produced no context for inspection.
Class signature
class sqlalchemy.exc.NoInspectionAvailable (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.NoReferenceError
Raised by ForeignKey
to indicate a reference cannot be resolved.
Class signature
class sqlalchemy.exc.NoReferenceError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.NoReferencedColumnError
Raised by ForeignKey
when the referred Column
cannot be located.
Class signature
class sqlalchemy.exc.NoReferencedColumnError (sqlalchemy.exc.NoReferenceError)
- method sqlalchemy.exc.NoReferencedColumnError.__init__(message: str, tname: str, cname: str)
exception sqlalchemy.exc.NoReferencedTableError
Raised by ForeignKey
when the referred Table
cannot be located.
Class signature
class sqlalchemy.exc.NoReferencedTableError (sqlalchemy.exc.NoReferenceError)
- method sqlalchemy.exc.NoReferencedTableError.__init__(message: str, tname: str)
exception sqlalchemy.exc.NoResultFound
A database result was required but none was found.
Changed in version 1.4: This exception is now part of the sqlalchemy.exc
module in Core, moved from the ORM. The symbol remains importable from sqlalchemy.orm.exc
.
Class signature
class sqlalchemy.exc.NoResultFound (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.NoSuchColumnError
A nonexistent column is requested from a Row
.
Class signature
class sqlalchemy.exc.NoSuchColumnError (sqlalchemy.exc.InvalidRequestError, builtins.KeyError
)
exception sqlalchemy.exc.NoSuchModuleError
Raised when a dynamically-loaded module (usually a database dialect) of a particular name cannot be located.
Class signature
class sqlalchemy.exc.NoSuchModuleError (sqlalchemy.exc.ArgumentError)
exception sqlalchemy.exc.NoSuchTableError
Table does not exist or is not visible to a connection.
Class signature
class sqlalchemy.exc.NoSuchTableError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.NotSupportedError
Wraps a DB-API NotSupportedError.
Class signature
class sqlalchemy.exc.NotSupportedError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.ObjectNotExecutableError
Raised when an object is passed to .execute() that can’t be executed as SQL.
New in version 1.1.
Class signature
class sqlalchemy.exc.ObjectNotExecutableError (sqlalchemy.exc.ArgumentError)
- method sqlalchemy.exc.ObjectNotExecutableError.__init__(target: Any)
exception sqlalchemy.exc.OperationalError
Wraps a DB-API OperationalError.
Class signature
class sqlalchemy.exc.OperationalError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.PendingRollbackError
A transaction has failed and needs to be rolled back before continuing.
New in version 1.4.
Class signature
class sqlalchemy.exc.PendingRollbackError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.ProgrammingError
Wraps a DB-API ProgrammingError.
Class signature
class sqlalchemy.exc.ProgrammingError (sqlalchemy.exc.DatabaseError)
exception sqlalchemy.exc.ResourceClosedError
An operation was requested from a connection, cursor, or other object that’s in a closed state.
Class signature
class sqlalchemy.exc.ResourceClosedError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.SADeprecationWarning
Issued for usage of deprecated APIs.
Class signature
class sqlalchemy.exc.SADeprecationWarning (sqlalchemy.exc.HasDescriptionCode, builtins.DeprecationWarning
)
attribute sqlalchemy.exc.SADeprecationWarning.deprecated_since: Optional[str] = None
Indicates the version that started raising this deprecation warning
exception sqlalchemy.exc.SAPendingDeprecationWarning
A similar warning as SADeprecationWarning, this warning is not used in modern versions of SQLAlchemy.
Class signature
class sqlalchemy.exc.SAPendingDeprecationWarning (builtins.PendingDeprecationWarning
)
attribute sqlalchemy.exc.SAPendingDeprecationWarning.deprecated_since: Optional[str] = None
Indicates the version that started raising this deprecation warning
exception sqlalchemy.exc.SATestSuiteWarning
warning for a condition detected during tests that is non-fatal
Currently outside of SAWarning so that we can work around tools like Alembic doing the wrong thing with warnings.
Class signature
class sqlalchemy.exc.SATestSuiteWarning (builtins.Warning
)
exception sqlalchemy.exc.SAWarning
Issued at runtime.
Class signature
class sqlalchemy.exc.SAWarning (sqlalchemy.exc.HasDescriptionCode, builtins.RuntimeWarning
)
exception sqlalchemy.exc.SQLAlchemyError
Generic error class.
Class signature
class sqlalchemy.exc.SQLAlchemyError (sqlalchemy.exc.HasDescriptionCode, builtins.Exception
)
exception sqlalchemy.exc.StatementError
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.
Class signature
class sqlalchemy.exc.StatementError (sqlalchemy.exc.SQLAlchemyError)
method sqlalchemy.exc.StatementError.__init__(message: str, statement: Optional[str], params: Optional[_AnyExecuteParams], orig: Optional[BaseException], hide_parameters: bool = False, code: Optional[str] = None, ismulti: Optional[bool] = None)
attribute sqlalchemy.exc.StatementError.ismulti: Optional[bool] = None
multi parameter passed to repr_params(). None is meaningful.
attribute sqlalchemy.exc.StatementError.orig: Optional[BaseException] = None
The original exception that was thrown.
attribute sqlalchemy.exc.StatementError.params: Optional[_AnyExecuteParams] = None
The parameter list being used when this exception occurred.
attribute sqlalchemy.exc.StatementError.statement: Optional[str] = None
The string SQL statement being invoked when this exception occurred.
exception sqlalchemy.exc.TimeoutError
Raised when a connection pool times out on getting a connection.
Class signature
class sqlalchemy.exc.TimeoutError (sqlalchemy.exc.SQLAlchemyError)
exception sqlalchemy.exc.UnboundExecutionError
SQL was attempted without a database connection to execute it on.
Class signature
class sqlalchemy.exc.UnboundExecutionError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.UnreflectableTableError
Table exists but can’t be reflected for some reason.
New in version 1.2.
Class signature
class sqlalchemy.exc.UnreflectableTableError (sqlalchemy.exc.InvalidRequestError)
exception sqlalchemy.exc.UnsupportedCompilationError
Raised when an operation is not supported by the given compiler.
See also
How do I render SQL expressions as strings, possibly with bound parameters inlined?
Compiler StrSQLCompiler can’t render element of type <element type>
Class signature
class sqlalchemy.exc.UnsupportedCompilationError (sqlalchemy.exc.CompileError)
- method sqlalchemy.exc.UnsupportedCompilationError.__init__(compiler: Union[Compiled, TypeCompiler], element_type: Type[ClauseElement], message: Optional[str] = None)