When and Why to Use SELECT FOR UPDATE in CockroachDB

CockroachDB has introduced SELECT FOR UPDATE to simplify handling of client-side transaction retry errors and improve performance. This feature allows applications to take explicit control of row-level locking on a per-statement basis, reducing the need for developers to implement retry-loops for contended transactions. Benchmarking with YCSB (Yahoo! Cloud Serving Benchmark) showed that enabling SELECT FOR UPDATE in CockroachDB 20.1 improved throughput, tail latency, and reduced the number of transaction retry errors compared to v19.2.