Required. The instance to list backups from. Values are of the form projects/{project}/instances/{instance}.

An expression that filters the list of returned backups. A filter expression consists of a field name, a comparison operator, and a value for filtering. The value must be a string, a number, or a boolean. The comparison operator must be one of: <, >, <=, >=, !=, =, or :. Colon : is the contains operator. Filter rules are not case sensitive. The following fields in the Backup are eligible for filtering: * name * database * state * create_time (and values are of the format YYYY-MM-DDTHH:MM:SSZ) * expire_time (and values are of the format YYYY-MM-DDTHH:MM:SSZ) * version_time (and values are of the format YYYY-MM-DDTHH:MM:SSZ) * size_bytes * backup_schedules You can combine multiple expressions by enclosing each expression in parentheses. By default, expressions are combined with AND logic, but you can specify AND, OR, and NOT logic explicitly. Here are a few examples: * name:Howl - The backup's name contains the string "howl". * database:prod - The database's name contains the string "prod". * state:CREATING - The backup is pending creation. * state:READY - The backup is fully created and ready for use. * (name:howl) AND (create_time < \"2018-03-28T14:50:00Z\") - The backup name contains the string "howl" and create_time of the backup is before 2018-03-28T14:50:00Z. * expire_time < \"2018-03-28T14:50:00Z\" - The backup expire_time is before 2018-03-28T14:50:00Z. * size_bytes > 10000000000 - The backup's size is greater than 10GB * backup_schedules:daily - The backup is created from a schedule with "daily" in its name.

Number of backups to be returned in the response. If 0 or less, defaults to the server's maximum allowed page size.

If non-empty, page_token should contain a next_page_token from a previous ListBackupsResponse to the same parent and with the same filter.