Code RoomLock escalation blocks writers
HardPrep Room Coding #2965

Lock escalation blocks writers

On-callDatabases & SQLConcurrencySenior–Staff~40 min

On SQL Server, the orders DB starts throwing widespread lock-timeout errors at 02:10 and writes back up across many unrelated tables, not just one. Dashboards: blocking-chain length spikes, and the blocking-tree root is a single session running a long analytics report that began at 02:00. That session holds escalated table-level (not row-level) locks on `orders` and `order_items`, blocking all writers behind it. A nightly reporting job was rescheduled this week to run during a busier window. Triage and explain the cascade.

What a strong answer looks like

Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.

0:00 of about 40 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.