File: //lib/python3/dist-packages/awscli/examples/lambda/update-event-source-mapping.rst
**To update the mapping between an event source and an AWS Lambda function**
The following ``update-event-source-mapping`` example updates the batch size to 8 in the specified mapping. ::
aws lambda update-event-source-mapping \
--uuid "a1b2c3d4-5678-90ab-cdef-11111EXAMPLE" \
--batch-size 8
Output::
{
"UUID": "a1b2c3d4-5678-90ab-cdef-11111EXAMPLE",
"StateTransitionReason": "USER_INITIATED",
"LastModified": 1569284520.333,
"BatchSize": 8,
"State": "Updating",
"FunctionArn": "arn:aws:lambda:us-west-2:123456789012:function:my-function",
"EventSourceArn": "arn:aws:sqs:us-west-2:123456789012:mySQSqueue"
}
For more information, see `AWS Lambda Event Source Mapping <https://docs.aws.amazon.com/lambda/latest/dg/invocation-eventsourcemapping.html>`__ in the *AWS Lambda Developer Guide*.