Principles Of Distributed Database Systems Exercise Solutions

: Implementation of ACID properties (Atomicity, Consistency, Isolation, Durability) across multiple sites.

(stored at Site B).The following execution sequence occurs under a Distributed Strict 2PL protocol: T1cap T sub 1 requests and obtains a Write Lock at Site A. T2cap T sub 2 requests and obtains a Write Lock at Site B. T1cap T sub 1 requests a Read Lock at Site B. (Blocked by T2cap T sub 2 T2cap T sub 2 requests a Write Lock at Site A. (Blocked by T1cap T sub 1 T1cap T sub 1 requests a Read Lock at Site B

If reply "NO", the Coordinator sends an "ABORT" message. the Coordinator sends an "ABORT" message.

Techniques like Peer-to-Peer Replication or Sharding (partitioning) allow data to be distributed across multiple sites to improve fault tolerance and performance. 2. Distributed Database Systems Exercise Solutions : Implementation of ACID properties (Atomicity

Exercises often provide a global algebraic query tree and ask you to transform it into a localized query tree.

Reliability protocols ensure that an atomic transaction executes completely across all participating nodes or fails cleanly everywhere. Two-Phase Commit (2PC) Execution Step-by-Step

Turning SQL into algebraic operations (Select, Project, Join).