Throttling SQL Server database cpu usage
Edited for clarity and consistency:


By the database itself? No. However, you can through the connection (what you should be trying to manage anyways) called the Resource Governor. 


CPU
MEMORY
Physical IO, depending on the version. 


There are a number of Concepts which the Docs explain in greater detail:

Resource Pool


a group of default, internal (cannot be changed), and custom made groups that have a set value on the amount of CPU, Memory, and Physical IO that a session may consume. 


Workload Group


a class of session requests that have  similar characteristics. These are mapped to  The appropriate resource pool and are set at the time of connection settings. Meaning the default database connect is used not the first USE statement or any statement afterwards. 


The governor must be activated Or configured.  A governor specific function is run against the connection's  default settings  and map to a workload group.

.  This workload is attached to a specific resource pool where the limitations are enforced on all subsequent sessions that occur out of the connection.

This function is the most important part and you should keep it simple. 

For more reading, visit the Docs:

Main Page -Resource Governor

Resource governor Resource pool

Research governor Workload group

Resource governor classifier function  | Docs Microsoft