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+---
+title: Use SKIP LOCKED for Non-Blocking Queue Processing
+impact: MEDIUM-HIGH
+impactDescription: 10x throughput for worker queues
+tags: skip-locked, queue, workers, concurrency
+---
+
+## Use SKIP LOCKED for Non-Blocking Queue Processing
+
+When multiple workers process a queue, SKIP LOCKED allows workers to process different rows without waiting.
+
+**Incorrect (workers block each other):**
+
+```sql
+-- Worker 1 and Worker 2 both try to get next job
+begin;
+select * from jobs where status = 'pending' order by created_at limit 1 for update;
+-- Worker 2 waits for Worker 1's lock to release!
+```
+
+**Correct (SKIP LOCKED for parallel processing):**
+
+```sql
+-- Each worker skips locked rows and gets the next available
+begin;
+select * from jobs
+where status = 'pending'
+order by created_at
+limit 1
+for update skip locked;
+
+-- Worker 1 gets job 1, Worker 2 gets job 2 (no waiting)
+
+update jobs set status = 'processing' where id = $1;
+commit;
+```
+
+Complete queue pattern:
+
+```sql
+-- Atomic claim-and-update in one statement
+update jobs
+set status = 'processing', worker_id = $1, started_at = now()
+where id = (
+  select id from jobs
+  where status = 'pending'
+  order by created_at
+  limit 1
+  for update skip locked
+)
+returning *;
+```
+
+Reference: [SELECT FOR UPDATE SKIP LOCKED](https://www.postgresql.org/docs/current/sql-select.html#SQL-FOR-UPDATE-SHARE)