In my last post, we saw how databases handle conflicts through different philosophies i.e., prevention, validation, versioning, and observation, allowing transactions to run concurrently without violating serializability. But avoiding or resolving conflicts isn’t the end of the story. Even after all conflicts are managed, the database still has…
In my last post, we saw how databases achieve concurrency by creating wiggle room for interleaving non-conflicting operations through conflict-free schedules. This ability to reoder independent operations without changing the final outcome is what gives serializable systems their performance edge. But we also saw that conflicting operations fix the relative…
In my previous blog, I explored how serializability ensures isolation across transactions while linearizability guarantees real-time consistency of single objects. This post builds on that discussion by diving deeper into serializability, essentially exploring how valid serial transaction orders are nothing but a means to achieve concurrency through conflict-free scheduling. We…
How do modern databases and distributed systems ensure correctness while allowing operations to run concurrently? Two foundational guarantees — serializability and linearizability — offer different answers depending on whether you care about logical correctness or real-time visibility. In this post, we’ll explore what they are, how they differ, and why it’…
In the previous post, we looked under the hood at how databases enforce isolation through locks, validations, and snapshots. Although these isolation levels were already introduced in the earlier post, we’ll revisit them here to clear up one of the most common sources of confusion i.e., the trio…