Key Takeaways

Active-active replication is a data-ownership problem first; conflict handlers only clean up what the ownership model failed to prevent.

Last-writer-wins converge every replica to the same value, but convergence is not correct: concurrent counter updates are silently discarded and both sites agree on the wrong number.

Delta resolution preserves every committed increment and decrement, yet it cannot protect an invariant such as "never sell more rooms than exist"; that requires a single owner or an escrowed quota.

Under clock skew, timestamp resolution quietly becomes "highest clock wins," so time synchronization belongs in the replication runbook.

Divergence tools such as Veridata detect replicas that disagree, not replicas that agree on a lost update, so business-level reconciliation must complement row comparison.

Executive Summary

Bi-directional Oracle GoldenGate lets two regions write the same tables, and its conflict detection and resolution (CDR) features make that look like…