# Lock compatibility

The following table shows the compatibility between lock types. "Yes" means that the lock types are compatible, while "No" means that they are incompatible.

Table 1. Lock Compatibility Matrix
Lock Type | Shared | Update | Exclusive
--- | --- | --- | ---
Shared | Yes | Yes | No
Update | Yes | No | No
Exclusive | No | No | No

Parent topic: Types and scope of locks in Derby systems
Related concepts
Exclusive locks
Shared locks
Update locks
Notes on locking
Related reference
Scope of locks