# exceptions
Gathers all exceptions thrown by ormar.
## AsyncOrmException Objects
```python
class AsyncOrmException(Exception)
```
Base ormar Exception
## ModelDefinitionError Objects
```python
class ModelDefinitionError(AsyncOrmException)
```
Raised for errors related to the model definition itself:
* setting @property_field on method with arguments other than func(self)
* defining a Field without required parameters
* defining a model with more than one primary_key
* defining a model without primary_key
* setting primary_key column as pydantic_only
## ModelError Objects
```python
class ModelError(AsyncOrmException)
```
Raised for initialization of model with non-existing field keyword.
## NoMatch Objects
```python
class NoMatch(AsyncOrmException)
```
Raised for database queries that has no matching result (empty result).
## MultipleMatches Objects
```python
class MultipleMatches(AsyncOrmException)
```
Raised for database queries that should return one row (i.e. get, first etc.)
but has multiple matching results in response.
## QueryDefinitionError Objects
```python
class QueryDefinitionError(AsyncOrmException)
```
Raised for errors in query definition:
* using contains or icontains filter with instance of the Model
* using Queryset.update() without filter and setting each flag to True
* using Queryset.delete() without filter and setting each flag to True
## RelationshipInstanceError Objects
```python
class RelationshipInstanceError(AsyncOrmException)
```
## ModelPersistenceError Objects
```python
class ModelPersistenceError(AsyncOrmException)
```
Raised for update of models without primary_key set (cannot retrieve from db)
or for saving a model with relation to unsaved model (cannot extract fk value).
## SignalDefinitionError Objects
```python
class SignalDefinitionError(AsyncOrmException)
```
Raised when non callable receiver is passed as signal callback.