X_DB_LOCK_TIMEOUT
Means
the statement waited past its lock_timeout
Typical cause
SQLSTATE 55P03 — usually a DDL statement queued behind a long transaction holding the same table, which then blocks every reader behind it.
Fix
x db diagnostics --json \| jq '.data.blockers.rows[] \| {pid, blockedBy, blockerState}' — end the blockedBy session or wait for it, then re-run the statement